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  • 1.
    Aartsen, M. G.
    et al.
    Univ Adelaide, Sch Chem & Phys, Adelaide, SA 5005, Australia..
    Abraham, K.
    Tech Univ Munich, D-85748 Garching, Germany..
    Ackermann, M.
    DESY, D-15735 Zeuthen, Germany..
    Adams, J.
    Univ Canterbury, Dept Phys & Astron, Christchurch 1, New Zealand..
    Aguilar, J. A.
    Univ Libre Bruxelles, Fac Sci, B-1050 Brussels, Belgium..
    Ahlers, M.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    Ahrens, M.
    Univ Stockholm, Dept Phys, Oskar Klein Ctr, S-10691 Stockholm, Sweden..
    Altmann, D.
    Univ Erlangen Nurnberg, Erlangen Ctr Astroparticle Phys, D-91058 Erlangen, Germany..
    Anderson, T.
    Penn State Univ, Dept Phys, University Pk, PA 16802 USA..
    Archinger, M.
    Johannes Gutenberg Univ Mainz, Inst Phys, D-55099 Mainz, Germany..
    Arguelles, C.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    Arlen, T. C.
    Penn State Univ, Dept Phys, University Pk, PA 16802 USA..
    Auffenberg, J.
    Rhein Westfal TH Aachen, Inst Phys 3, D-52056 Aachen, Germany..
    Bai, X.
    South Dakota Sch Mines & Technol, Dept Phys, Rapid City, SD 57701 USA..
    Barwick, S. W.
    Univ Calif Irvine, Dept Phys & Astron, Irvine, CA 92697 USA..
    Baum, V.
    Johannes Gutenberg Univ Mainz, Inst Phys, D-55099 Mainz, Germany..
    Bay, R.
    Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA..
    Beatty, J. J.
    Ohio State Univ, Dept Phys, Columbus, OH 43210 USA.;Ohio State Univ, Ctr Cosmol & Astroparticle Phys, Columbus, OH 43210 USA.;Ohio State Univ, Dept Astron, Columbus, OH 43210 USA..
    Tjus, J. Becker
    Ruhr Univ Bochum, Fak Phys & Astron, D-44780 Bochum, Germany..
    Becker, K. -H
    Beiser, E.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    BenZvi, S.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    Berghaus, P.
    DESY, D-15735 Zeuthen, Germany..
    Berley, D.
    Univ Maryland, Dept Phys, College Pk, MD 20742 USA..
    Bernardini, E.
    DESY, D-15735 Zeuthen, Germany..
    Bernhard, A.
    Tech Univ Munich, D-85748 Garching, Germany..
    Besson, D. Z.
    Univ Kansas, Dept Phys & Astron, Lawrence, KS 66045 USA..
    Binder, G.
    Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA.;Lawrence Berkeley Natl Lab, Berkeley, CA USA..
    Bindig, D.
    Univ Wuppertal, Dept Phys, D-42119 Wuppertal, Germany..
    Bissok, M.
    Rhein Westfal TH Aachen, Inst Phys 3, D-52056 Aachen, Germany..
    Blaufuss, E.
    Univ Maryland, Dept Phys, College Pk, MD 20742 USA..
    Blumenthal, J.
    Rhein Westfal TH Aachen, Inst Phys 3, D-52056 Aachen, Germany..
    Boersma, David J.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Högenergifysik.
    Bohm, C.
    Univ Stockholm, Dept Phys, Oskar Klein Ctr, S-10691 Stockholm, Sweden..
    Boerner, M.
    TU Dortmund Univ, Dept Phys, D-44221 Dortmund, Germany..
    Bos, F.
    Ruhr Univ Bochum, Fak Phys & Astron, D-44780 Bochum, Germany..
    Bose, D.
    Sungkyunkwan Univ, Dept Phys, Suwon 440 746, South Korea..
    Boeser, S.
    Johannes Gutenberg Univ Mainz, Inst Phys, D-55099 Mainz, Germany..
    Botner, Olga
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Högenergifysik.
    Braun, J.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    Brayeur, L.
    Vrije Univ Brussel, Dienst ELEM, Brussels, Belgium..
    Bretz, H. -P
    Brown, A. M.
    Univ Canterbury, Dept Phys & Astron, Christchurch 1, New Zealand..
    Buzinsky, N.
    Univ Alberta, Dept Phys, Edmonton, AB T6G 2E1, Canada..
    Casey, J.
    Georgia Inst Technol, Sch Phys, Atlanta, GA 30332 USA.;Georgia Inst Technol, Ctr Relativist Astrophys, Atlanta, GA 30332 USA..
    Casier, M.
    Vrije Univ Brussel, Dienst ELEM, Brussels, Belgium..
    Cheung, E.
    Univ Maryland, Dept Phys, College Pk, MD 20742 USA..
    Chirkin, D.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    Christov, A.
    Univ Geneva, Dept phys nucl & corpusculaire, CH-1211 Geneva, Switzerland..
    Christy, B.
    Univ Maryland, Dept Phys, College Pk, MD 20742 USA..
    Clark, K.
    Univ Toronto, Dept Phys, Toronto, ON M5S 1A7, Canada..
    Classen, L.
    Univ Erlangen Nurnberg, Erlangen Ctr Astroparticle Phys, D-91058 Erlangen, Germany..
    Coenders, S.
    Tech Univ Munich, D-85748 Garching, Germany..
    Cowen, D. F.
    Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA.;Penn State Univ, Dept Phys, University Pk, PA 16802 USA..
    Silva, A. H. Cruz
    DESY, D-15735 Zeuthen, Germany..
    Daughhetee, J.
    Georgia Inst Technol, Sch Phys, Atlanta, GA 30332 USA.;Georgia Inst Technol, Ctr Relativist Astrophys, Atlanta, GA 30332 USA..
    Davis, J. C.
    Ohio State Univ, Dept Phys, Columbus, OH 43210 USA.;Ohio State Univ, Ctr Cosmol & Astroparticle Phys, Columbus, OH 43210 USA..
    Day, M.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    de Andre, J. P. A. M.
    Michigan State Univ, Dept Phys & Astron, E Lansing, MI 48824 USA..
    De Clercq, C.
    Vrije Univ Brussel, Dienst ELEM, Brussels, Belgium..
    Dembinski, H.
    Univ Delaware, Bartol Res Inst, Dept Phys & Astron, Newark, DE 19716 USA..
    De Ridder, S.
    Univ Ghent, Dept Phys & Astron, B-9000 Ghent, Belgium..
    Desiati, P.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    de Vries, K. D.
    Vrije Univ Brussel, Dienst ELEM, Brussels, Belgium..
    de Wasseige, G.
    Vrije Univ Brussel, Dienst ELEM, Brussels, Belgium..
    de With, M.
    Humboldt Univ, D-12489 Berlin, Germany..
    DeYoung, T.
    Michigan State Univ, Dept Phys & Astron, E Lansing, MI 48824 USA..
    Diaz-Velez, J. C.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    Dumm, J. P.
    Univ Stockholm, Dept Phys, Oskar Klein Ctr, S-10691 Stockholm, Sweden..
    Dunkman, M.
    Penn State Univ, Dept Phys, University Pk, PA 16802 USA..
    Eagan, R.
    Penn State Univ, Dept Phys, University Pk, PA 16802 USA..
    Eberhardt, B.
    Johannes Gutenberg Univ Mainz, Inst Phys, D-55099 Mainz, Germany..
    Ehrhardt, T.
    Johannes Gutenberg Univ Mainz, Inst Phys, D-55099 Mainz, Germany..
    Eichmann, B.
    Ruhr Univ Bochum, Fak Phys & Astron, D-44780 Bochum, Germany..
    Euler, Sebastian
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Högenergifysik.
    Evenson, P. A.
    Univ Delaware, Bartol Res Inst, Dept Phys & Astron, Newark, DE 19716 USA..
    Fadiran, O.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    Fahey, S.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    Fazely, A. R.
    Southern Univ, Dept Phys, Baton Rouge, LA 70813 USA..
    Fedynitch, A.
    Ruhr Univ Bochum, Fak Phys & Astron, D-44780 Bochum, Germany..
    Feintzeig, J.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    Felde, J.
    Univ Maryland, Dept Phys, College Pk, MD 20742 USA..
    Filimonov, K.
    Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA..
    Finley, C.
    Univ Stockholm, Dept Phys, Oskar Klein Ctr, S-10691 Stockholm, Sweden..
    Fischer-Wasels, T.
    Univ Wuppertal, Dept Phys, D-42119 Wuppertal, Germany..
    Flis, S.
    Univ Stockholm, Dept Phys, Oskar Klein Ctr, S-10691 Stockholm, Sweden..
    Fuchs, T.
    TU Dortmund Univ, Dept Phys, D-44221 Dortmund, Germany..
    Glagla, M.
    Rhein Westfal TH Aachen, Inst Phys 3, D-52056 Aachen, Germany..
    Gaisser, T. K.
    Univ Delaware, Bartol Res Inst, Dept Phys & Astron, Newark, DE 19716 USA..
    Gaior, R.
    Chiba Univ, Dept Phys, Chiba 2638522, Japan..
    Gallagher, J.
    Univ Wisconsin, Dept Astron, Madison, WI 53706 USA..
    Gerhardt, L.
    Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA.;Lawrence Berkeley Natl Lab, Berkeley, CA USA..
    Ghorbani, K.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    Gier, D.
    Rhein Westfal TH Aachen, Inst Phys 3, D-52056 Aachen, Germany..
    Gladstone, L.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    Gluesenkamp, T.
    DESY, D-15735 Zeuthen, Germany..
    Goldschmidt, A.
    Lawrence Berkeley Natl Lab, Berkeley, CA USA..
    Golup, G.
    Vrije Univ Brussel, Dienst ELEM, Brussels, Belgium..
    Gonzalez, J. G.
    Univ Delaware, Bartol Res Inst, Dept Phys & Astron, Newark, DE 19716 USA..
    Gora, D.
    DESY, D-15735 Zeuthen, Germany..
    Grant, D.
    Univ Alberta, Dept Phys, Edmonton, AB T6G 2E1, Canada..
    Gretskov, P.
    Rhein Westfal TH Aachen, Inst Phys 3, D-52056 Aachen, Germany..
    Groh, J. C.
    Penn State Univ, Dept Phys, University Pk, PA 16802 USA..
    Gross, A.
    Tech Univ Munich, D-85748 Garching, Germany..
    Ha, C.
    Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA.;Lawrence Berkeley Natl Lab, Berkeley, CA USA..
    Haack, C.
    Rhein Westfal TH Aachen, Inst Phys 3, D-52056 Aachen, Germany..
    Ismail, A. Haj
    Univ Ghent, Dept Phys & Astron, B-9000 Ghent, Belgium..
    Hallgren, Allan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Högenergifysik.
    Halzen, F.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    Hansmann, B.
    Rhein Westfal TH Aachen, Inst Phys 3, D-52056 Aachen, Germany..
    Hanson, K.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    Hebecker, D.
    Humboldt Univ, D-12489 Berlin, Germany..
    Heereman, D.
    Univ Libre Bruxelles, Fac Sci, B-1050 Brussels, Belgium..
    Helbing, K.
    Univ Wuppertal, Dept Phys, D-42119 Wuppertal, Germany..
    Hellauer, R.
    Univ Maryland, Dept Phys, College Pk, MD 20742 USA..
    Hellwig, D.
    Rhein Westfal TH Aachen, Inst Phys 3, D-52056 Aachen, Germany..
    Hickford, S.
    Univ Wuppertal, Dept Phys, D-42119 Wuppertal, Germany..
    Hignight, J.
    Michigan State Univ, Dept Phys & Astron, E Lansing, MI 48824 USA..
    Hill, G. C.
    Univ Adelaide, Sch Chem & Phys, Adelaide, SA 5005, Australia..
    Hoffman, K. D.
    Univ Maryland, Dept Phys, College Pk, MD 20742 USA..
    Hoffmann, R.
    Univ Wuppertal, Dept Phys, D-42119 Wuppertal, Germany..
    Holzapfel, K.
    Tech Univ Munich, D-85748 Garching, Germany..
    Homeier, A.
    Univ Bonn, Inst Phys, D-53115 Bonn, Germany..
    Hoshina, K.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    Huang, F.
    Penn State Univ, Dept Phys, University Pk, PA 16802 USA..
    Huber, M.
    Tech Univ Munich, D-85748 Garching, Germany..
    Huelsnitz, W.
    Univ Maryland, Dept Phys, College Pk, MD 20742 USA..
    Hulth, P. O.
    Univ Stockholm, Dept Phys, Oskar Klein Ctr, S-10691 Stockholm, Sweden..
    Hultqvist, K.
    Univ Stockholm, Dept Phys, Oskar Klein Ctr, S-10691 Stockholm, Sweden..
    In, S.
    Sungkyunkwan Univ, Dept Phys, Suwon 440 746, South Korea..
    Ishihara, A.
    Chiba Univ, Dept Phys, Chiba 2638522, Japan..
    Jacobi, E.
    DESY, D-15735 Zeuthen, Germany..
    Japaridze, G. S.
    Clark Atlanta Univ, CTSPS, Atlanta, GA 30314 USA..
    Jero, K.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    Jurkovic, M.
    Tech Univ Munich, D-85748 Garching, Germany..
    Kaminsky, B.
    DESY, D-15735 Zeuthen, Germany..
    Kappes, A.
    Univ Erlangen Nurnberg, Erlangen Ctr Astroparticle Phys, D-91058 Erlangen, Germany..
    Karg, T.
    DESY, D-15735 Zeuthen, Germany..
    Karle, A.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    Kauer, M.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA.;Yale Univ, Dept Phys, New Haven, CT 06520 USA..
    Keivani, A.
    Penn State Univ, Dept Phys, University Pk, PA 16802 USA..
    Kelley, J. L.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    Kemp, J.
    Rhein Westfal TH Aachen, Inst Phys 3, D-52056 Aachen, Germany..
    Kheirandish, A.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    Kiryluk, J.
    SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA..
    Klaes, J.
    Univ Wuppertal, Dept Phys, D-42119 Wuppertal, Germany..
    Klein, S. R.
    Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA.;Lawrence Berkeley Natl Lab, Berkeley, CA USA..
    Kohnen, G.
    Univ Mons, B-7000 Mons, Belgium..
    Kolanoski, H.
    Humboldt Univ, D-12489 Berlin, Germany..
    Konietz, R.
    Rhein Westfal TH Aachen, Inst Phys 3, D-52056 Aachen, Germany..
    Koob, A.
    Rhein Westfal TH Aachen, Inst Phys 3, D-52056 Aachen, Germany..
    Koepke, L.
    Johannes Gutenberg Univ Mainz, Inst Phys, D-55099 Mainz, Germany..
    Kopper, C.
    Univ Alberta, Dept Phys, Edmonton, AB T6G 2E1, Canada..
    Kopper, S.
    Univ Wuppertal, Dept Phys, D-42119 Wuppertal, Germany.;DESY, D-15735 Zeuthen, Germany..
    Koskinen, D. J.
    Univ Copenhagen, Niels Bohr Inst, DK-2100 Copenhagen, Denmark..
    Kowalski, M.
    Humboldt Univ, D-12489 Berlin, Germany..
    Krings, K.
    Tech Univ Munich, D-85748 Garching, Germany..
    Kroll, G.
    Johannes Gutenberg Univ Mainz, Inst Phys, D-55099 Mainz, Germany..
    Kroll, M.
    Ruhr Univ Bochum, Fak Phys & Astron, D-44780 Bochum, Germany..
    Kunnen, J.
    Vrije Univ Brussel, Dienst ELEM, Brussels, Belgium..
    Kurahashi, N.
    Drexel Univ, Dept Phys, Philadelphia, PA 19104 USA..
    Kuwabara, T.
    Chiba Univ, Dept Phys, Chiba 2638522, Japan..
    Labare, M.
    Univ Ghent, Dept Phys & Astron, B-9000 Ghent, Belgium..
    Lanfranchi, J. L.
    Penn State Univ, Dept Phys, University Pk, PA 16802 USA..
    Larson, M. J.
    Univ Copenhagen, Niels Bohr Inst, DK-2100 Copenhagen, Denmark..
    Lesiak-Bzdak, M.
    SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA..
    Leuermann, M.
    Rhein Westfal TH Aachen, Inst Phys 3, D-52056 Aachen, Germany..
    Leuner, J.
    Rhein Westfal TH Aachen, Inst Phys 3, D-52056 Aachen, Germany..
    Luenemann, J.
    Johannes Gutenberg Univ Mainz, Inst Phys, D-55099 Mainz, Germany..
    Madsen, J.
    Univ Wisconsin, Dept Phys, River Falls, WI 54022 USA..
    Maggi, G.
    Vrije Univ Brussel, Dienst ELEM, Brussels, Belgium..
    Mahn, K. B. M.
    Michigan State Univ, Dept Phys & Astron, E Lansing, MI 48824 USA..
    Maruyama, R.
    Yale Univ, Dept Phys, New Haven, CT 06520 USA..
    Mase, K.
    Chiba Univ, Dept Phys, Chiba 2638522, Japan..
    Matis, H. S.
    Lawrence Berkeley Natl Lab, Berkeley, CA USA..
    Maunu, R.
    Univ Maryland, Dept Phys, College Pk, MD 20742 USA..
    McNally, F.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    Meagher, K.
    Univ Libre Bruxelles, Fac Sci, B-1050 Brussels, Belgium..
    Medici, M.
    Univ Copenhagen, Niels Bohr Inst, DK-2100 Copenhagen, Denmark..
    Meli, A.
    Univ Ghent, Dept Phys & Astron, B-9000 Ghent, Belgium..
    Menne, T.
    TU Dortmund Univ, Dept Phys, D-44221 Dortmund, Germany..
    Merino, G.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    Meures, T.
    Univ Libre Bruxelles, Fac Sci, B-1050 Brussels, Belgium..
    Miarecki, S.
    Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA.;Lawrence Berkeley Natl Lab, Berkeley, CA USA..
    Middell, E.
    DESY, D-15735 Zeuthen, Germany..
    Middlemas, E.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    Miller, J.
    Vrije Univ Brussel, Dienst ELEM, Brussels, Belgium..
    Mohrmann, L.
    DESY, D-15735 Zeuthen, Germany..
    Montaruli, T.
    Univ Geneva, Dept phys nucl & corpusculaire, CH-1211 Geneva, Switzerland..
    Morse, R.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    Nahnhauer, R.
    DESY, D-15735 Zeuthen, Germany..
    Naumann, U.
    Univ Wuppertal, Dept Phys, D-42119 Wuppertal, Germany..
    Niederhausen, H.
    SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA..
    Nowicki, S. C.
    Univ Alberta, Dept Phys, Edmonton, AB T6G 2E1, Canada..
    Nygren, D. R.
    Lawrence Berkeley Natl Lab, Berkeley, CA USA..
    Obertacke, A.
    Univ Wuppertal, Dept Phys, D-42119 Wuppertal, Germany..
    Olivas, A.
    Univ Maryland, Dept Phys, College Pk, MD 20742 USA..
    Omairat, A.
    Univ Wuppertal, Dept Phys, D-42119 Wuppertal, Germany..
    O'Murchadha, A.
    Univ Libre Bruxelles, Fac Sci, B-1050 Brussels, Belgium..
    Palczewski, T.
    Univ Alabama, Dept Phys & Astron, Tuscaloosa, AL 35487 USA..
    Paul, L.
    Rhein Westfal TH Aachen, Inst Phys 3, D-52056 Aachen, Germany..
    Pepper, J. A.
    Univ Alabama, Dept Phys & Astron, Tuscaloosa, AL 35487 USA..
    de los Heros, Carlos. Perez
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Högenergifysik.
    Pfendner, C.
    Ohio State Univ, Dept Phys, Columbus, OH 43210 USA.;Ohio State Univ, Ctr Cosmol & Astroparticle Phys, Columbus, OH 43210 USA..
    Pieloth, D.
    TU Dortmund Univ, Dept Phys, D-44221 Dortmund, Germany..
    Pinat, E.
    Univ Libre Bruxelles, Fac Sci, B-1050 Brussels, Belgium..
    Posselt, J.
    Univ Wuppertal, Dept Phys, D-42119 Wuppertal, Germany..
    Price, P. B.
    Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA..
    Przybylski, G. T.
    Lawrence Berkeley Natl Lab, Berkeley, CA USA..
    Puetz, J.
    Rhein Westfal TH Aachen, Inst Phys 3, D-52056 Aachen, Germany..
    Quinnan, M.
    Penn State Univ, Dept Phys, University Pk, PA 16802 USA..
    Raedel, L.
    Rhein Westfal TH Aachen, Inst Phys 3, D-52056 Aachen, Germany..
    Rameez, M.
    Univ Geneva, Dept phys nucl & corpusculaire, CH-1211 Geneva, Switzerland..
    Rawlins, K.
    Univ Alaska Anchorage, Dept Phys & Astron, Anchorage, AK 99508 USA..
    Redl, P.
    Univ Maryland, Dept Phys, College Pk, MD 20742 USA..
    Reimann, R.
    Rhein Westfal TH Aachen, Inst Phys 3, D-52056 Aachen, Germany..
    Relich, M.
    Chiba Univ, Dept Phys, Chiba 2638522, Japan..
    Resconi, E.
    Tech Univ Munich, D-85748 Garching, Germany..
    Rhode, W.
    TU Dortmund Univ, Dept Phys, D-44221 Dortmund, Germany..
    Richman, M.
    Drexel Univ, Dept Phys, Philadelphia, PA 19104 USA..
    Richter, S.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    Riedel, B.
    Univ Alberta, Dept Phys, Edmonton, AB T6G 2E1, Canada..
    Robertson, S.
    Univ Adelaide, Sch Chem & Phys, Adelaide, SA 5005, Australia..
    Rongen, M.
    Rhein Westfal TH Aachen, Inst Phys 3, D-52056 Aachen, Germany..
    Rott, C.
    Sungkyunkwan Univ, Dept Phys, Suwon 440 746, South Korea..
    Ruhe, T.
    TU Dortmund Univ, Dept Phys, D-44221 Dortmund, Germany..
    Ruzybayev, B.
    Univ Delaware, Bartol Res Inst, Dept Phys & Astron, Newark, DE 19716 USA..
    Ryckbosch, D.
    Univ Ghent, Dept Phys & Astron, B-9000 Ghent, Belgium..
    Saba, S. M.
    Ruhr Univ Bochum, Fak Phys & Astron, D-44780 Bochum, Germany..
    Sabbatini, L.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    Sander, H. -G
    Sandrock, A.
    TU Dortmund Univ, Dept Phys, D-44221 Dortmund, Germany..
    Sandroos, J.
    Univ Copenhagen, Niels Bohr Inst, DK-2100 Copenhagen, Denmark..
    Sarkar, S.
    Univ Copenhagen, Niels Bohr Inst, DK-2100 Copenhagen, Denmark.;Univ Oxford, Dept Phys, Oxford OX1 3NP, England..
    Schatto, K.
    Johannes Gutenberg Univ Mainz, Inst Phys, D-55099 Mainz, Germany..
    Scheriau, F.
    TU Dortmund Univ, Dept Phys, D-44221 Dortmund, Germany..
    Schimp, M.
    Rhein Westfal TH Aachen, Inst Phys 3, D-52056 Aachen, Germany..
    Schmidt, T.
    Univ Maryland, Dept Phys, College Pk, MD 20742 USA..
    Schmitz, M.
    TU Dortmund Univ, Dept Phys, D-44221 Dortmund, Germany..
    Schoenen, S.
    Rhein Westfal TH Aachen, Inst Phys 3, D-52056 Aachen, Germany..
    Schoeneberg, S.
    Ruhr Univ Bochum, Fak Phys & Astron, D-44780 Bochum, Germany..
    Schoenwald, A.
    DESY, D-15735 Zeuthen, Germany..
    Schukraft, A.
    Rhein Westfal TH Aachen, Inst Phys 3, D-52056 Aachen, Germany..
    Schulte, L.
    Univ Bonn, Inst Phys, D-53115 Bonn, Germany..
    Seckel, D.
    Univ Delaware, Bartol Res Inst, Dept Phys & Astron, Newark, DE 19716 USA..
    Seunarine, S.
    Univ Wisconsin, Dept Phys, River Falls, WI 54022 USA..
    Shanidze, R.
    DESY, D-15735 Zeuthen, Germany..
    Smith, M. W. E.
    Penn State Univ, Dept Phys, University Pk, PA 16802 USA..
    Soldin, D.
    Univ Wuppertal, Dept Phys, D-42119 Wuppertal, Germany..
    Spiczak, G. M.
    Univ Wisconsin, Dept Phys, River Falls, WI 54022 USA..
    Spiering, C.
    DESY, D-15735 Zeuthen, Germany..
    Stahlberg, M.
    Rhein Westfal TH Aachen, Inst Phys 3, D-52056 Aachen, Germany..
    Stamatikos, M.
    Ohio State Univ, Dept Phys, Columbus, OH 43210 USA.;Ohio State Univ, Ctr Cosmol & Astroparticle Phys, Columbus, OH 43210 USA..
    Stanev, T.
    Univ Delaware, Bartol Res Inst, Dept Phys & Astron, Newark, DE 19716 USA..
    Stanisha, N. A.
    Penn State Univ, Dept Phys, University Pk, PA 16802 USA..
    Stasik, A.
    DESY, D-15735 Zeuthen, Germany..
    Stezelberger, T.
    Lawrence Berkeley Natl Lab, Berkeley, CA USA..
    Stokstad, R. G.
    Lawrence Berkeley Natl Lab, Berkeley, CA USA..
    Stoessl, A.
    DESY, D-15735 Zeuthen, Germany..
    Strahler, E. A.
    Vrije Univ Brussel, Dienst ELEM, Brussels, Belgium..
    Ström, Richard
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Högenergifysik.
    Strotjohann, N. L.
    DESY, D-15735 Zeuthen, Germany..
    Sullivan, G. W.
    Univ Maryland, Dept Phys, College Pk, MD 20742 USA..
    Sutherland, M.
    Ohio State Univ, Dept Phys, Columbus, OH 43210 USA.;Ohio State Univ, Ctr Cosmol & Astroparticle Phys, Columbus, OH 43210 USA..
    Taavola, Henric
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Högenergifysik.
    Taboada, I.
    Georgia Inst Technol, Sch Phys, Atlanta, GA 30332 USA.;Georgia Inst Technol, Ctr Relativist Astrophys, Atlanta, GA 30332 USA..
    Ter-Antonyan, S.
    Southern Univ, Dept Phys, Baton Rouge, LA 70813 USA..
    Terliuk, A.
    DESY, D-15735 Zeuthen, Germany..
    Tesic, G.
    Penn State Univ, Dept Phys, University Pk, PA 16802 USA..
    Tilav, S.
    Univ Delaware, Bartol Res Inst, Dept Phys & Astron, Newark, DE 19716 USA..
    Toale, P. A.
    Univ Alabama, Dept Phys & Astron, Tuscaloosa, AL 35487 USA..
    Tobin, M. N.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    Tosi, D.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    Tselengidou, M.
    Univ Erlangen Nurnberg, Erlangen Ctr Astroparticle Phys, D-91058 Erlangen, Germany..
    Unger, E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Högenergifysik.
    Usner, M.
    DESY, D-15735 Zeuthen, Germany..
    Vallecorsa, S.
    Univ Geneva, Dept phys nucl & corpusculaire, CH-1211 Geneva, Switzerland..
    van Eijndhoven, N.
    Vrije Univ Brussel, Dienst ELEM, Brussels, Belgium..
    Vandenbroucke, J.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    van Santen, J.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    Vanheule, S.
    Univ Ghent, Dept Phys & Astron, B-9000 Ghent, Belgium..
    Veenkamp, J.
    Tech Univ Munich, D-85748 Garching, Germany..
    Vehring, M.
    Rhein Westfal TH Aachen, Inst Phys 3, D-52056 Aachen, Germany..
    Voge, M.
    Univ Bonn, Inst Phys, D-53115 Bonn, Germany..
    Vraeghe, M.
    Univ Ghent, Dept Phys & Astron, B-9000 Ghent, Belgium..
    Walck, C.
    Univ Stockholm, Dept Phys, Oskar Klein Ctr, S-10691 Stockholm, Sweden..
    Wallraff, M.
    Rhein Westfal TH Aachen, Inst Phys 3, D-52056 Aachen, Germany..
    Wandkowsky, N.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    Weaver, Ch.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    Wendt, C.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    Westerhoff, S.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    Whelan, B. J.
    Univ Adelaide, Sch Chem & Phys, Adelaide, SA 5005, Australia..
    Whitehorn, N.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    Wichary, C.
    Rhein Westfal TH Aachen, Inst Phys 3, D-52056 Aachen, Germany..
    Wiebe, K.
    Johannes Gutenberg Univ Mainz, Inst Phys, D-55099 Mainz, Germany..
    Wiebusch, C. H.
    Rhein Westfal TH Aachen, Inst Phys 3, D-52056 Aachen, Germany..
    Wille, L.
    Univ Wisconsin, Dept Phys, Wisconsin IceCube Particle Astrophys Ctr, Madison, WI 53706 USA..
    Williams, D. R.
    Univ Alabama, Dept Phys & Astron, Tuscaloosa, AL 35487 USA..
    Wissing, H.
    Univ Maryland, Dept Phys, College Pk, MD 20742 USA..
    Wolf, M.
    Univ Stockholm, Dept Phys, Oskar Klein Ctr, S-10691 Stockholm, Sweden..
    Wood, T. R.
    Univ Alberta, Dept Phys, Edmonton, AB T6G 2E1, Canada..
    Woschnagg, K.
    Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA..
    Xu, D. L.
    Univ Alabama, Dept Phys & Astron, Tuscaloosa, AL 35487 USA..
    Xu, X. W.
    Southern Univ, Dept Phys, Baton Rouge, LA 70813 USA..
    Xu, Y.
    SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA..
    Yanez, J. P.
    DESY, D-15735 Zeuthen, Germany..
    Yodh, G.
    Univ Calif Irvine, Dept Phys & Astron, Irvine, CA 92697 USA..
    Yoshida, S.
    Chiba Univ, Dept Phys, Chiba 2638522, Japan..
    Zarzhitsky, P.
    Univ Alabama, Dept Phys & Astron, Tuscaloosa, AL 35487 USA..
    Zoll, M.
    Univ Stockholm, Dept Phys, Oskar Klein Ctr, S-10691 Stockholm, Sweden..
    Search for dark matter annihilation in the Galactic Center with IceCube-792015Ingår i: European Physical Journal C, ISSN 1434-6044, E-ISSN 1434-6052, Vol. 75, nr 10, artikel-id 492Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The Milky Way is expected to be embedded in a halo of dark matter particles, with the highest density in the central region, and decreasing density with the halo-centric radius. Dark matter might be indirectly detectable at Earth through a flux of stable particles generated in dark matter annihilations and peaked in the direction of the Galactic Center. We present a search for an excess flux of muon (anti-) neutrinos from dark matter annihilation in the Galactic Center using the cubic-kilometer-sized IceCube neutrino detector at the South Pole. There, the Galactic Center is always seen above the horizon. Thus, new and dedicated veto techniques against atmospheric muons are required to make the southern hemisphere accessible for IceCube. We used 319.7 live-days of data from IceCube operating in its 79-string configuration during 2010 and 2011. No neutrino excess was found and the final result is compatible with the background. We present upper limits on the self-annihilation cross-section, < sAv >, for WIMP masses ranging from 30GeV up to 10TeV, assuming cuspy (NFW) and flat-cored (Burkert) dark matter halo profiles, reaching down to similar or equal to 4 . 10(-24) cm(3) s(-1), and similar or equal to 2.6 . 10(-23) cm(3) s(-1) for the nu(nu) over bar channel, respectively.

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  • 2. Aho-Mantila, L.
    et al.
    Andersson Sundén, Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Asp, E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Binda, Federico
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Cecconello, Marco
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Conroy, Sean
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Dzysiuk, Nataliia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Ericsson, Göran
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Eriksson, Jacob
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Hellesen, Carl
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Hjalmarsson, Anders
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Possnert, Göran
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Sjöstrand, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Skiba, Mateusz
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Weiszflog, Matthias
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Zychor, I.
    Assessment of SOLPS5.0 divertor solutions with drifts and currents against L-mode experiments in ASDEX Upgrade and JET2017Ingår i: Plasma Physics and Controlled Fusion, ISSN 0741-3335, E-ISSN 1361-6587, Vol. 59, nr 3, artikel-id 035003Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The divertor solutions obtained with the plasma edge modelling tool SOLPS5.0 are discussed. The code results are benchmarked against carefully analysed L-mode discharges at various density levels with and without impurity seeding in the full-metal tokamaks ASDEX Upgrade and JET. The role of the cross-field drifts and currents in the solutions is analysed in detail, and the improvements achieved by fully activating the drift and current terms in view of matching the experimental signals are addressed. The persisting discrepancies are also discussed.

  • 3.
    Aiba, N.
    et al.
    Natl Inst Quantum & Radiol Sci & Technol, Rokkasho, Aomori, Japan.
    Andersson Sundén, Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Andersson Sundén, Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Cecconello, Marco
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Conroy, Sean
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Dzysiuk, Nataliia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Ericsson, Göran
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Eriksson, Jacob
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Hellesen, Carl
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Hjalmarsson, Anders
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Possnert, Göran
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Possnert, Göran
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Skiba, Mateusz
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Weiszflog, Matthias
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Zychor, I.
    Natl Ctr Nucl Res, Otwock, Poland.
    Analysis of ELM stability with extended MHD models in JET, JT-60U and future JT-60SA tokamak plasmas2018Ingår i: Plasma Physics and Controlled Fusion, ISSN 0741-3335, E-ISSN 1361-6587, Vol. 60, nr 1, artikel-id 014032Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The stability with respect to a peeling-ballooning mode (PBM) was investigated numerically with extended MHD simulation codes in JET, JT-60U and future JT-60SA plasmas. The MINERVA-DI code was used to analyze the linear stability, including the effects of rotation and ion diamagnetic drift (omega(*i)), in JET-ILW and JT-60SA plasmas, and the JOREK code was used to simulate nonlinear dynamics with rotation, viscosity and resistivity in JT-60U plasmas. It was validated quantitatively that the ELM trigger condition in JET-ILW plasmas can be reasonably explained by taking into account both the rotation and omega(*i) effects in the numerical analysis. When deuterium poloidal rotation is evaluated based on neoclassical theory, an increase in the effective charge of plasma destabilizes the PBM because of an acceleration of rotation and a decrease in omega(*i). The difference in the amount of ELM energy loss in JT-60U plasmas rotating in opposite directions was reproduced qualitatively with JOREK. By comparing the ELM affected areas with linear eigenfunctions, it was confirmed that the difference in the linear stability property, due not to the rotation direction but to the plasma density profile, is thought to be responsible for changing the ELM energy loss just after the ELM crash. A predictive study to determine the pedestal profiles in JT-60SA was performed by updating the EPED1 model to include the rotation and w*i effects in the PBM stability analysis. It was shown that the plasma rotation predicted with the neoclassical toroidal viscosity degrades the pedestal performance by about 10% by destabilizing the PBM, but the pressure pedestal height will be high enough to achieve the target parameters required for the ITER-like shape inductive scenario in JT-60SA.

  • 4. Aiba, N.
    et al.
    Andersson Sundén, Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Binda, Federico
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Cecconello, Marco
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Conroy, Sean
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Dzysiuk, Nataliia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Ericsson, Göran
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Eriksson, Jacob
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Hellesen, Carl
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Hjalmarsson, Anders
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Possnert, Göran
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Sjöstrand, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Skiba, Mateusz
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Weiszflog, Matthias
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Zychor, I.
    Numerical analysis of ELM stability with rotation and ion diamagnetic drift effects in JET2017Ingår i: Nuclear Fusion, ISSN 0029-5515, E-ISSN 1741-4326, Vol. 57, nr 12, artikel-id 126001Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Stability to the type-I edge localized mode (ELM) in JET plasmas was investigated numerically by analyzing the stability to a peeling-ballooning mode with the effects of plasma rotation and ion diamagnetic drift. The numerical analysis was performed by solving the extended Frieman-Rotenberg equation with the MINERVA-DI code. To take into account these effects in the stability analysis self-consistently, the procedure of JET equilibrium reconstruction was updated to include the profiles of ion temperature and toroidal rotation, which are determined based on the measurement data in experiments. With the new procedure and MINERVA-DI, it was identified that the stability analysis including the rotation effect can explain the ELM trigger condition in JET with ITER like wall (JET-ILW), though the stability in JET with carbon wall (JET-C) is hardly affected by rotation. The key difference is that the rotation shear in JET-ILW plasmas analyzed in this study is larger than that in JET-C ones, the shear which enhances the dynamic pressure destabilizing a peeling-ballooning mode. In addition, the increase of the toroidal mode number of the unstable MHD mode determining the ELM trigger condition is also important when the plasma density is high in JET-ILW. Though such modes with high toroidal mode number are strongly stabilized by the ion diamagnetic drift effect, it was found that plasma rotation can sometimes overcome this stabilizing effect and destabilizes the peeling-ballooning modes in JET-ILW.

  • 5.
    Aiempanakit, Montri
    et al.
    Linkoping University.
    Aijaz, Asim
    Linkoping University.
    Helmersson, Ulf
    Linkoping University.
    Kubart, Tomas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Hysteresis effect in reactive high power impulse magnetron sputtering of metal oxides2011Konferensbidrag (Refereegranskat)
    Abstract [en]

    In order to get high deposition rate and good film properties, the stabilization of the transition zone between the metallic and compound modes is beneficial. We have shown earlier that at least in some cases, HiPIMS can reduce hysteresis effect in reactive sputtering. In our previous work, mechanisms for the suppression/elimination of the hysteresis effect have been suggested. Reactive HiPIMS can suppress/eliminate the hysteresis effect in the range of optimum frequency [1] lead to the process stability during the deposition with high deposition rate. The mechanisms behind this optimum frequency may relate with high erosion rate during the pulse [2,3] and gas rarefaction effect in front of the target [4]. 

     

    In this contribution, reactive sputtering process using high power impulse magnetron sputtering (HiPIMS) has been studied with focus on the gas rarefaction. Through variations in the sputtering conditions such as pulse frequencies, peak powers, and target area, their effect on the shape of current waveforms have been analyzed. The current waveforms in compound mode are strongly affected. Our experiments show that the shape and amplitude of peak current cannot be explained by the change of the secondary electron yield due to target oxidation only. Reduced rarefaction in compound mode contributes to the observed very high peak current values.

  • 6.
    Aikio, A. T.
    et al.
    Univ Oulu, Ionospher Phys Unit, Oulu, Finland.
    Vanhamaeki, H.
    Kyushu Univ, Int Ctr Space Weather Sci & Educ, Fukuoka, Japan;Univ Oulu, Ionospher Phys Unit, Oulu, Finland.
    Workayehu, A. B.
    Univ Oulu, Ionospher Phys Unit, Oulu, Finland.
    Virtanen, I. I.
    Univ Oulu, Ionospher Phys Unit, Oulu, Finland.
    Kauristie, K.
    Finnish Meteorol Inst, Helsinki, Finland.
    Juusola, L.
    Finnish Meteorol Inst, Helsinki, Finland.
    Buchert, Stephan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Knudsen, D.
    Univ Calgary, Dept Phys & Astron, Calgary, AB, Canada.
    Swarm Satellite and EISCAT Radar Observations of a Plasma Flow Channel in the Auroral Oval Near Magnetic Midnight2018Ingår i: Journal of Geophysical Research - Space Physics, ISSN 2169-9380, E-ISSN 2169-9402, Vol. 123, nr 6, s. 5140-5158Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We present Swarm satellite and EISCAT radar observations of electrodynamical parameters in the midnight sector at high latitudes. The most striking feature is a plasma flow channel located equatorward of the polar cap boundary within the dawn convection cell. The flow channel is 1.5 degrees wide in latitude and contains southward electric field of 150 mV/m, corresponding to eastward plasma velocities of 3,300 m/s in the F-region ionosphere. The theoretically computed ion temperature enhancement produced by the observed ion velocity is in accordance with the measured one by the EISCAT radar. The total width of the auroral oval is about 10 degrees in latitude. While the poleward part is electric field dominant with low conductivity and the flow channel, the equatorward part is conductivity dominant with at least five auroral arcs. The main part of the westward electrojet flows in the conductivity dominant part, but it extends to the electric field dominant part. According to Kamide and Kokubun (1996), the whole midnight sector westward electrojet is expected to be conductivity dominant, so the studied event challenges the traditional view. The flow channel is observed after substorm onset. We suggest that the observed flow channel, which is associated with a 13-kV horizontal potential difference, accommodates increased nightside plasma flows during the substorm expansion phase as a result of reconnection in the near-Earth magnetotail.

  • 7.
    Akbari, H.
    et al.
    Univ Colorado, Lab Atmospher & Space Phys, Boulder, CO 80309 USA.
    Andersson, L.
    Univ Colorado, Lab Atmospher & Space Phys, Boulder, CO 80309 USA.
    Andrews, David J.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Malaspina, D.
    Univ Colorado, Lab Atmospher & Space Phys, Boulder, CO 80309 USA.
    Benna, M.
    NASA, Goddard Space Flight Ctr, Greenbelt, MD USA.
    Ergun, R.
    Univ Colorado, Lab Atmospher & Space Phys, Boulder, CO 80309 USA.
    In Situ Electron Density From Active Sounding: The Influence of the Spacecraft Wake2019Ingår i: Geophysical Research Letters, ISSN 0094-8276, E-ISSN 1944-8007, Vol. 46, nr 17-18, s. 10250-10256Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Results obtained in the Martian ionosphere by the Langmuir Probe and Waves instrument aboard the Mars Atmosphere and Volatile EvolutioN Mission spacecraft are presented. The results include ionospheric electron densities determined from the frequency of Langmuir waves. Since the amplitude of thermal Langmuir waves is often below the instrument's detection level, Langmuir Probe and Waves excites these waves by injecting into the plasma a 3.3-V white noise signal. Electric field spectral measurements obtained shortly after the excitation show a resonance line at frequencies slightly below the local plasma frequency. The observed resonance line is interpreted to originate from plasma waves excited in the wake behind the spacecraft. These results reveal an important phenomenon in electron density estimation from stimulated Langmuir waves. The observed phenomenon, not previously reported by earlier missions, may be a common process in active sounding that can affect in situ electron density measurements.

  • 8.
    Al Moulla, Khaled
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Turbulence at MHD and sub-ion scales in the magnetosheath of Saturn: a comparative study between quasi-perpendicular and quasi-parallel bow shocks using in-situ Cassini data2018Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Syftet med detta projekt är att undersöka de spektrala egenskaperna hos turbulens i Saturnus magnetoskikt, med in-situ-mätningar av magnetfältet från Cassini-rymdsonden. Enligt modeller av inkompressibla, turbulenta fluider, är energispektrumet i det intertiala omfånget proportionellt mot frekvensen upphöjd i -5/3, vilket har observerats i den jordnära Solvinden men inte i det jordiska magnetoskiktet förutom nära magnetopausen. 120 tidsintervall för när Cassini befinner sig inuti magnetoskiktet identifieras — 40 styck i kategorierna bakom kvasi-vinkelräta bogchockar, bakom kvasi-parallella bogchockar, och inuti mellersta delen av magnetoskiktet. Effektspektraltätheten beräknas därefter för varje intervall, med logaritmiska regressioner på MHD- och subjon-skalorna som separeras av jongyrofrekvensen. Resultaten verkar tyda på liknande beteende som i Jordens magnetoskikt, utan märkvärdig skillnad mellan kvasi-vinkelräta och kvasi-parallella fall förutom något brantare exponenter på MHD-skalan för de förnämnda. Dessa observationer bekräftar bogchokens roll i förstörandet av den fullt utvecklade turbulensen i Solvinden, därmed förklarande avsaknaden av det inertiala omfånget.

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  • 9.
    Ala-Lahti, Matti
    et al.
    Univ Helsinki, Dept Phys, Helsinki, Finland..
    Dimmock, Andrew P.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Pulkkinen, Tuija I.
    Univ Michigan, Dept Climate & Space Sci & Engn, Ann Arbor, MI 48109 USA.;Aalto Univ, Dept Elect & Nanoengn Engn, Espoo, Finland..
    Good, Simon W.
    Univ Helsinki, Dept Phys, Helsinki, Finland..
    Yordanova, Emiliya
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Turc, Lucile
    Univ Helsinki, Dept Phys, Helsinki, Finland..
    Kilpua, Emilia K. J.
    Univ Helsinki, Dept Phys, Helsinki, Finland..
    Transmission of an ICME Sheath Into the Earth's Magnetosheath and the Occurrence of Traveling Foreshocks2021Ingår i: Journal of Geophysical Research - Space Physics, ISSN 2169-9380, E-ISSN 2169-9402, Vol. 126, nr 12, artikel-id e2021JA029896Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The transmission of a sheath region driven by an interplanetary coronal mass ejection into the Earth's magnetosheath is studied by investigating in situ magnetic field measurements upstream and downstream of the bow shock during an ICME sheath passage on 15 May 2005. We observe three distinct intervals in the immediate upstream region that included a southward magnetic field component and are traveling foreshocks. These traveling foreshocks were observed in the quasi-parallel bow shock that hosted backstreaming ions and magnetic fluctuations at ultralow frequencies. The intervals constituting traveling foreshocks in the upstream survive transmission to the Earth's magnetosheath, where their magnetic field, and particularly the southward component, was significantly amplified. Our results further suggest that the magnetic field fluctuations embedded in an ICME sheath may survive the transmission if their frequency is below ∼0.01 Hz. Although one of the identified intervals was coherent, extending across the ICME sheath and being long-lived, predicting ICME sheath magnetic fields that may transmit to the Earth's magnetosheath from the upstream at L1 observations has ambiguity. This can result from the strong spatial variability of the ICME sheath fields in the longitudinal direction, or alternatively from the ICME sheath fields developing substantially within the short time it takes the plasma to propagate from L1 to the bow shock. This study demonstrates the complex interplay ICME sheaths have with the Earth's magnetosphere when passing by the planet.

  • 10.
    Ala-Lahti, Matti
    et al.
    Univ Helsinki, Dept Phys, Helsinki, Finland.
    Kilpua, Emilia K. J.
    Univ Helsinki, Dept Phys, Helsinki, Finland.
    Soucek, Jan
    Czech Acad Sci, Inst Atmospher Phys, Prague, Czech Republic.
    Pulkkinen, Tuija, I
    Univ Michigan, Dept Climate & Space Sci & Engn, Ann Arbor, MI 48109 USA;Aalto Univ, Sch Elect Engn, Espoo, Finland.
    Dimmock, Andrew P.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Alfven Ion Cyclotron Waves in Sheath Regions Driven by Interplanetary Coronal Mass Ejections2019Ingår i: Journal of Geophysical Research - Space Physics, ISSN 2169-9380, E-ISSN 2169-9402, Vol. 124, nr 6, s. 3893-3909Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We report on a statistical analysis of the occurrence and properties of Alfven ion cyclotron (AIC) waves in sheath regions driven by interplanetary coronal mass ejections (ICMEs). We have developed an automated algorithm to identify AIC wave events from magnetic field data and apply it to investigate 91 ICME sheath regions recorded by the Wind spacecraft. Our analysis focuses on waves generated by the ion cyclotron instability. AIC waves are observed to be frequent structures in ICME-driven sheaths, and their occurrence is the highest in the vicinity of the shock. Together with previous studies, our results imply that the shock compression has a crucial role in generating wave activity in ICME sheaths. AIC waves tend to have their frequency below the ion cyclotron frequency, and, in general, occur in plasma that is stable with respect to the ion cyclotron instability and has lower ion beta(parallel to) than mirror modes. The results suggest that the ion beta anisotropy beta(perpendicular to)/beta(parallel to) > 1 appearing in ICME sheaths is regulated by both ion cyclotron and mirror instabilities.

  • 11.
    Ala-Lahti, Matti M.
    et al.
    Univ Helsinki, Dept Phys, POB 64, Helsinki, Finland.
    Kilpua, Emilia K. J.
    Univ Helsinki, Dept Phys, POB 64, Helsinki, Finland.
    Dimmock, Andrew P.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen. Aalto Univ, Sch Elect Engn, Espoo, Finland.
    Osmane, Adnane
    Aalto Univ, Sch Elect Engn, Espoo, Finland.
    Pulkkinen, Tuija
    Aalto Univ, Sch Elect Engn, Espoo, Finland.
    Soucek, Jan
    Czech Acad Sci, Inst Atmospher Phys, Prague, Czech Republic.
    Statistical analysis of mirror mode waves in sheath regions driven by interplanetary coronal mass ejection2018Ingår i: Annales Geophysicae, ISSN 0992-7689, E-ISSN 1432-0576, Vol. 36, nr 3, s. 793-808Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We present a comprehensive statistical analysis of mirror mode waves and the properties of their plasma surroundings in sheath regions driven by interplanetary coronal mass ejection (ICME). We have constructed a semi-automated method to identify mirror modes from the magnetic field data. We analyze 91 ICME sheath regions from January 1997 to April 2015 using data from the Wind spacecraft. The results imply that similarly to planetary magnetosheaths, mirror modes are also common structures in ICME sheaths. However, they occur almost exclusively as dip-like structures and in mirror stable plasma. We observe mirror modes throughout the sheath, from the bow shock to the ICME leading edge, but their amplitudes are largest closest to the shock. We also find that the shock strength (measured by Alfven Mach number) is the most important parameter in controlling the occurrence of mirror modes. Our findings suggest that in ICME sheaths the dominant source of free energy for mirror mode generation is the shock compression. We also suggest that mirror modes that are found deeper in the sheath are remnants from earlier times of the sheath evolution, generated also in the vicinity of the shock.

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  • 12.
    Alberti, Tommaso
    et al.
    INAF Ist Astrofis & Planetol Spaziali, Rome, Italy.
    Consolini, Giuseppe
    INAF Ist Astrofis & Planetol Spaziali, , Rome, Italy.
    Carbone, Vincenzo
    Univ Calabria, Dipartimento Fis, Arcavacata Di Rende, Italy.
    Yordanova, Emiliya
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Marcucci, Maria Federica
    INAF Ist Astrofis & Planetol Spaziali, Rome, Italy.
    De Michelis, Paola
    Ist Nazl Geofis & Vulcanol, Rome, Italy.
    Multifractal and Chaotic Properties of Solar Wind at MHD and Kinetic Domains: An Empirical Mode Decomposition Approach2019Ingår i: Entropy, E-ISSN 1099-4300, Vol. 21, nr 3, artikel-id 320Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Turbulence, intermittency, and self-organized structures in space plasmas can be investigated by using a multifractal formalism mostly based on the canonical structure function analysis with fixed constraints about stationarity, linearity, and scales. Here, the Empirical Mode Decomposition (EMD) method is firstly used to investigate timescale fluctuations of the solar wind magnetic field components; then, by exploiting the local properties of fluctuations, the structure function analysis is used to gain insights into the scaling properties of both inertial and kinetic/dissipative ranges. Results show that while the inertial range dynamics can be described in a multifractal framework, characterizing an unstable fixed point of the system, the kinetic/dissipative range dynamics is well described by using a monofractal approach, because it is a stable fixed point of the system, unless it has a higher degree of complexity and chaos.

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  • 13.
    Alho, M.
    et al.
    Univ Helsinki, Dept Phys, Helsinki, Finland..
    Battarbee, M.
    Univ Helsinki, Dept Phys, Helsinki, Finland..
    Pfau-Kempf, Y.
    Univ Helsinki, Dept Phys, Helsinki, Finland..
    Khotyaintsev, Yuri V.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Nakamura, R.
    Austrian Acad Sci, Space Res Inst, Linz, Austria..
    Cozzani, G.
    Univ Helsinki, Dept Phys, Helsinki, Finland..
    Ganse, U.
    Univ Helsinki, Dept Phys, Helsinki, Finland..
    Turc, L.
    Univ Helsinki, Dept Phys, Helsinki, Finland..
    Johlander, A.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen. Univ Helsinki, Dept Phys, Helsinki, Finland..
    Horaites, K.
    Univ Helsinki, Dept Phys, Helsinki, Finland..
    Tarvus, V
    Univ Helsinki, Dept Phys, Helsinki, Finland..
    Zhou, H.
    Univ Helsinki, Dept Phys, Helsinki, Finland..
    Grandin, M.
    Univ Helsinki, Dept Phys, Helsinki, Finland..
    Dubart, M.
    Univ Helsinki, Dept Phys, Helsinki, Finland..
    Papadakis, K.
    Univ Helsinki, Dept Phys, Helsinki, Finland..
    Suni, J.
    Univ Helsinki, Dept Phys, Helsinki, Finland..
    George, H.
    Univ Helsinki, Dept Phys, Helsinki, Finland..
    Bussov, M.
    Univ Helsinki, Dept Phys, Helsinki, Finland..
    Palmroth, M.
    Univ Helsinki, Dept Phys, Helsinki, Finland.;Finnish Meteorol Inst, Helsinki, Finland..
    Electron Signatures of Reconnection in a Global eVlasiator Simulation2022Ingår i: Geophysical Research Letters, ISSN 0094-8276, E-ISSN 1944-8007, Vol. 49, nr 14, artikel-id e2022GL098329Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Geospace plasma simulations have progressed toward more realistic descriptions of the solar wind-magnetosphere interaction from magnetohydrodynamic to hybrid ion-kinetic, such as the state-of-the-art Vlasiator model. Despite computational advances, electron scales have been out of reach in a global setting. eVlasiator, a novel Vlasiator submodule, shows for the first time how electromagnetic fields driven by global hybrid-ion kinetics influence electrons, resulting in kinetic signatures. We analyze simulated electron distributions associated with reconnection sites and compare them with Magnetospheric Multiscale (MMS) spacecraft observations. Comparison with MMS shows that key electron features, such as reconnection inflows, heated outflows, flat-top distributions, and bidirectional streaming, are in remarkable agreement. Thus, we show that many reconnection-related features can be reproduced despite strongly truncated electron physics and an ion-scale spatial resolution. Ion-scale dynamics and ion-driven magnetic fields are shown to be significantly responsible for the environment that produces electron dynamics observed by spacecraft in near-Earth plasmas.

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  • 14.
    Alinder, Simon
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Effect of the convective electric field on the ion number density around a low activity comet2017Studentarbete övrigt, 5 poäng / 7,5 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Vigren et al. (2015) presents an integral expression to calculate the ion number density around a low activity comet immersed in the solar wind's convective electric field. A certain parameter of the integral takes values of either 1 or 0 depending on whether a corresponding ion trajectory is feasible or not. The criteria used in the paper has been found not to be strict enough, yielding overestimated ion number densities in the cometary wake. The present project finds two new options for the criteria, one analytical and one numerical. The new numerical condition is tested in the same computations done in the original paper and compares the results of the old and new criteria. The new conditionis found to correct the previous error.

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  • 15.
    Alinder, Simon
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi.
    Electron cooling in a cometary coma2017Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Rymdsonden Rosetta från ESA undersökte kometen 67P/Churyumov Gerasimenkounder mer än två år, från augusti 2014 till slutet av september 2016.En Langumirprob användes för att undersökta plasmamiljön runt kometen, tillexempel elektronernas termiska energi. Den observerade termiska energin förelektronerna (eller elektrontemperaturen) var ganska hög, ca 5-10 eV undernästan hela uppdraget, men när kometen var nära perihelium detekterade instrumentenäven kalla elektroner, med en energi under 1 eV, distinkta från devarma. En hypotes är att dessa kalla elektroner bildas nära kärnan av att varmaelektroner genomgår inelastiska kollisioner med den neutrala gasen och tapparsin energi. I detta projekt utvecklar vi en modell för att studera elektronernasbeteende i koman. Modellen tar hänsyn till kollisioner med neutrala vattenmolekylersåväl som påverkan av ett radiellt ambipolärt elektriskt fält.

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  • 16.
    Allen, R. C.
    et al.
    Johns Hopkins Appl Phys Lab, Laurel, MD 20723 USA..
    Cernuda, I
    Univ Alcala De Henares, Space Res Grp, Madrid, Spain..
    Pacheco, D.
    Christian Albrechts Univ Kiel, Inst Expt & Angewande Phys, D-24118 Kiel, Germany..
    Berger, L.
    Christian Albrechts Univ Kiel, Inst Expt & Angewande Phys, D-24118 Kiel, Germany..
    Xu, Z. G.
    Christian Albrechts Univ Kiel, Inst Expt & Angewande Phys, D-24118 Kiel, Germany..
    von Forstner, J. L. Freiherr
    Christian Albrechts Univ Kiel, Inst Expt & Angewande Phys, D-24118 Kiel, Germany..
    Rodriguez-Pacheco, J.
    Univ Alcala De Henares, Space Res Grp, Madrid, Spain..
    Wimmer-Schweingruber, R. F.
    Christian Albrechts Univ Kiel, Inst Expt & Angewande Phys, D-24118 Kiel, Germany..
    Ho, G. C.
    Johns Hopkins Appl Phys Lab, Laurel, MD 20723 USA..
    Mason, G. M.
    Johns Hopkins Appl Phys Lab, Laurel, MD 20723 USA..
    Vines, S. K.
    Johns Hopkins Appl Phys Lab, Laurel, MD 20723 USA..
    Khotyaintsev, Yuri V.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Horbury, T.
    Imperial Coll, London, England..
    Maksimovic, M.
    Univ Paris Diderot, Observ Paris, Sorbonne Univ, CNRS,LESIA,Univ PSL, Sorbonne Paris Cite,5 Pl Jules Janssen, F-92195 Meudon, France..
    Hadid, L. Z.
    Univ Paris Saclay, Observ Paris, Sorbonne Univ, Ecole Polytech,CNRS,LPP, Paris, France..
    Volwerk, M.
    Austrian Acad Sci, Space Res Inst, Graz, Austria..
    Dimmock, Andrew P.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Sorriso-Valvo, Luca
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen. CNR ISTP Ist Sci & Tecnol Plasmi, Via Amendola 122-D, I-70126 Bari, Italy..
    Stergiopoulou, Katerina
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Andrews, G. B.
    Johns Hopkins Appl Phys Lab, Laurel, MD 20723 USA..
    Angelini, V
    Imperial Coll, London, England..
    Bale, S. D.
    Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA.;Univ Calif Berkeley, Phys Dept, Berkeley, CA 94720 USA..
    Boden, S.
    Christian Albrechts Univ Kiel, Inst Expt & Angewande Phys, D-24118 Kiel, Germany.;DSI Datensicherheit GmbH, Rodendamm 34, D-28816 Stuhr, Germany..
    Boettcher, S. , I
    Chust, T.
    Univ Paris Saclay, Observ Paris, Sorbonne Univ, Ecole Polytech,CNRS,LPP, Paris, France..
    Eldrum, S.
    Christian Albrechts Univ Kiel, Inst Expt & Angewande Phys, D-24118 Kiel, Germany..
    Espada, P. P.
    Univ Alcala De Henares, Space Res Grp, Madrid, Spain..
    Lara, F. Espinosa
    Univ Alcala De Henares, Space Res Grp, Madrid, Spain..
    Evans, V
    Imperial Coll, London, England..
    Gomez-Herrero, R.
    Univ Alcala De Henares, Space Res Grp, Madrid, Spain..
    Hayes, J. R.
    Johns Hopkins Appl Phys Lab, Laurel, MD 20723 USA..
    Hellin, A. M.
    Univ Alcala De Henares, Space Res Grp, Madrid, Spain..
    Kollhoff, A.
    Christian Albrechts Univ Kiel, Inst Expt & Angewande Phys, D-24118 Kiel, Germany..
    Krasnoselskikh, V
    CNRS, LPC2E, 3A Ave Rech Sci, Orleans, France..
    Kretzschmar, M.
    CNRS, LPC2E, 3A Ave Rech Sci, Orleans, France.;Univ Orleans, Orleans, France..
    Kuehl, P.
    Christian Albrechts Univ Kiel, Inst Expt & Angewande Phys, D-24118 Kiel, Germany..
    Kulkarni, S. R.
    Christian Albrechts Univ Kiel, Inst Expt & Angewande Phys, D-24118 Kiel, Germany.;Deutsch Elektronen Synchrotron DESY, Platanenallee 6, D-15738 Zeuthen, Germany..
    Lees, W. J.
    Johns Hopkins Appl Phys Lab, Laurel, MD 20723 USA..
    Lorfevre, E.
    CNES, Toulouse, France..
    Martin, C.
    Christian Albrechts Univ Kiel, Inst Expt & Angewande Phys, D-24118 Kiel, Germany.;German Aerosp Ctr, Dept Extrasolar Planets & Atmospheres, Berlin, Germany..
    O'Brien, H.
    Imperial Coll, London, England..
    Plettemeier, D.
    Tech Univ Dresden, Dresden, Germany..
    Polo, O. R.
    Univ Alcala De Henares, Space Res Grp, Madrid, Spain..
    Prieto, M.
    Univ Alcala De Henares, Space Res Grp, Madrid, Spain..
    Ravanbakhsh, A.
    Christian Albrechts Univ Kiel, Inst Expt & Angewande Phys, D-24118 Kiel, Germany.;Max Planck Inst Solar Syst Res, Gottingen, Germany..
    Sanchez-Prieto, S.
    Univ Alcala De Henares, Space Res Grp, Madrid, Spain..
    Schlemm, C. E.
    Johns Hopkins Appl Phys Lab, Laurel, MD 20723 USA..
    Seifert, H.
    Johns Hopkins Appl Phys Lab, Laurel, MD 20723 USA..
    Soucek, J.
    Czech Acad Sci, Inst Atmospher Phys, Prague, Czech Republic..
    Steller, M.
    Austrian Acad Sci, Space Res Inst, Graz, Austria..
    Stverak, S.
    Czech Acad Sci, Astron Inst, Prague, Czech Republic..
    Terasa, J. C.
    Christian Albrechts Univ Kiel, Inst Expt & Angewande Phys, D-24118 Kiel, Germany..
    Travnicek, P.
    Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA.;Czech Acad Sci, Astron Inst, Prague, Czech Republic..
    Tyagi, K.
    Johns Hopkins Appl Phys Lab, Laurel, MD 20723 USA.;Univ Colorado, LASP, Boulder, CO 80309 USA..
    Vaivads, Andris
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen. Royal Inst Technol, Sch Elect Engn & Comp Sci, Dept Space & Plasma Phys, Stockholm, Sweden..
    Vecchio, A.
    Univ Paris Diderot, Observ Paris, Sorbonne Univ, CNRS,LESIA,Univ PSL, Sorbonne Paris Cite,5 Pl Jules Janssen, F-92195 Meudon, France.;Radboud Univ Nijmegen, Res Inst Math Astrophys & Particle Phys, Nijmegen, Netherlands..
    Yedla, M.
    Christian Albrechts Univ Kiel, Inst Expt & Angewande Phys, D-24118 Kiel, Germany.;Max Planck Inst Solar Syst Res, Gottingen, Germany..
    Energetic ions in the Venusian system: Insights from the first Solar Orbiter flyby2021Ingår i: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 656, artikel-id A7Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The Solar Orbiter flyby of Venus on 27 December 2020 allowed for an opportunity to measure the suprathermal to energetic ions in the Venusian system over a large range of radial distances to better understand the acceleration processes within the system and provide a characterization of galactic cosmic rays near the planet. Bursty suprathermal ion enhancements (up to similar to 10 keV) were observed as far as similar to 50R(V) downtail. These enhancements are likely related to a combination of acceleration mechanisms in regions of strong turbulence, current sheet crossings, and boundary layer crossings, with a possible instance of ion heating due to ion cyclotron waves within the Venusian tail. Upstream of the planet, suprathermal ions are observed that might be related to pick-up acceleration of photoionized exospheric populations as far as 5R(V) upstream in the solar wind as has been observed before by missions such as Pioneer Venus Orbiter and Venus Express. Near the closest approach of Solar Orbiter, the Galactic cosmic ray (GCR) count rate was observed to decrease by approximately 5 percent, which is consistent with the amount of sky obscured by the planet, suggesting a negligible abundance of GCR albedo particles at over 2 R-V. Along with modulation of the GCR population very close to Venus, the Solar Orbiter observations show that the Venusian system, even far from the planet, can be an effective accelerator of ions up to similar to 30 keV. This paper is part of a series of the first papers from the Solar Orbiter Venus flyby.

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  • 17.
    Allen, R. C.
    et al.
    Univ New Hampshire, Ctr Space Sci, Durham, NH 03824 USA..
    Zhang, J. -C
    Kistler, L. M.
    Univ New Hampshire, Ctr Space Sci, Durham, NH 03824 USA..
    Spence, H. E.
    Univ New Hampshire, Ctr Space Sci, Durham, NH 03824 USA..
    Lin, R. -L
    Klecker, B.
    Max Planck Inst Extraterr Phys, D-85748 Garching, Germany..
    Dunlop, M. W.
    Rutherford Appleton Lab, Div Space Sci, Harwell, Oxon, England..
    André, Mats
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Jordanova, V. K.
    Los Alamos Natl Lab, Los Alamos, NM USA..
    A statistical study of EMIC waves observed by Cluster: 1. Wave properties2015Ingår i: Journal of Geophysical Research - Space Physics, ISSN 2169-9380, E-ISSN 2169-9402, Vol. 120, nr 7, s. 5574-5592Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Electromagnetic ion cyclotron (EMIC) waves are an important mechanism for particle energization and losses inside the magnetosphere. In order to better understand the effects of these waves on particle dynamics, detailed information about the occurrence rate, wave power, ellipticity, normal angle, energy propagation angle distributions, and local plasma parameters are required. Previous statistical studies have used in situ observations to investigate the distribution of these parameters in the magnetic local time versus L-shell (MLT-L) frame within a limited magnetic latitude (MLAT) range. In this study, we present a statistical analysis of EMIC wave properties using 10years (2001-2010) of data from Cluster, totaling 25,431min of wave activity. Due to the polar orbit of Cluster, we are able to investigate EMIC waves at all MLATs and MLTs. This allows us to further investigate the MLAT dependence of various wave properties inside different MLT sectors and further explore the effects of Shabansky orbits on EMIC wave generation and propagation. The statistical analysis is presented in two papers. This paper focuses on the wave occurrence distribution as well as the distribution of wave properties. The companion paper focuses on local plasma parameters during wave observations as well as wave generation proxies.

  • 18.
    Allmann-Rahn, F.
    et al.
    Ruhr Univ Bochum, Universitatsstr 150, D-44801 Bochum, Germany..
    Grauer, R.
    Ruhr Univ Bochum, Universitatsstr 150, D-44801 Bochum, Germany..
    Kormann, Katharina
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för beräkningsvetenskap. Ruhr Univ Bochum, Universitatsstr 150, D-44801 Bochum, Germany..
    A parallel low-rank solver for the six-dimensional Vlasov-Maxwell equations2022Ingår i: Journal of Computational Physics, ISSN 0021-9991, E-ISSN 1090-2716, Vol. 469, artikel-id 111562Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Continuum Vlasov simulations can be utilized for highly accurate modelling of fully kinetic plasmas. Great progress has been made recently regarding the applicability of the method in realistic plasma configurations. However, a reduction of the high computational cost that is inherent to fully kinetic simulations would be desirable, especially at high velocity space resolutions. For this purpose, low-rank approximations can be employed. The so far available low-rank solvers are restricted to either electrostatic systems or low dimensionality and can therefore not be applied to most space, astrophysical and fusion plasmas. In this paper we present a new parallel low-rank solver for the full six-dimensional electromagnetic Vlasov-Maxwell equations that can utilize distributed memory architectures. Special care is taken to ensure the conservation of mass and a good representation of Gauss's law. The low-rank Vlasov solver is applied to standard benchmark problems of plasma turbulence and magnetic reconnection and compared to the full grid method. It yields accurate results at significantly reduced computational cost.

  • 19.
    Alm, L.
    et al.
    Univ New Hampshire, Space Sci Ctr, Durham, NH 03824 USA..
    Argall, M. R.
    Univ New Hampshire, Space Sci Ctr, Durham, NH 03824 USA..
    Torbert, R. B.
    Univ New Hampshire, Space Sci Ctr, Durham, NH 03824 USA.;Southwest Res Inst, San Antonio, TX USA..
    Farrugia, C. J.
    Univ New Hampshire, Space Sci Ctr, Durham, NH 03824 USA..
    Burch, J. L.
    Southwest Res Inst, San Antonio, TX USA..
    Ergun, R. E.
    Univ Colorado, Lab Atmospher & Space Phys, Boulder, CO 80309 USA..
    Russell, C. T.
    Univ Calif Los Angeles, IGPP EPSS, Los Angeles, CA USA..
    Strangeway, R. J.
    Univ Calif Los Angeles, IGPP EPSS, Los Angeles, CA USA..
    Khotyaintsev, Yuri V.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Lindqvist, P. -A
    Marklund, G. T.
    KTH Royal Inst Technol, Stockholm, Sweden..
    Giles, B. L.
    NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA..
    Shuster, J.
    NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.;Univ Maryland, Coll Comp Math & Nat Sci, College Pk, MD 20742 USA..
    EDR signatures observed by MMS in the 16 October event presented in a 2-D parametric space2017Ingår i: Journal of Geophysical Research - Space Physics, ISSN 2169-9380, E-ISSN 2169-9402, Vol. 122, nr 3, s. 3262-3276Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We present a method for mapping the position of satellites relative to the X line using the measured B-L and B-N components of the magnetic field and apply it to the Magnetospheric multiscale (MMS) encounter with the electron diffusion region (EDR) which occurred on 13:07 UT on 16 October 2015. Mapping the data to our parametric space succeeds in capturing many of the signatures associated with magnetic reconnection and the electron diffusion region. This offers a method for determining where in the reconnection region the satellites were located. In addition, parametric mapping can also be used to present data from numerical simulations. This facilitates comparing data from simulations with data from in situ observations as one can avoid the complicated process using boundary motion analysis to determine the geometry of the reconnection region. In parametric space we can identify the EDR based on the collocation of several reconnection signatures, such as electron nongyrotropy, electron demagnetization, parallel electric fields, and energy dissipation. The EDR extends 2-3km in the normal direction and in excess of 20km in the tangential direction. It is clear that the EDR occurs on the magnetospheric side of the topological X line, which is expected in asymmetric reconnection. Furthermore, we can observe a north-south asymmetry, where the EDR occurs north of the peak in out-of-plane current, which may be due to the small but finite guide field.

  • 20.
    Alm, Love
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    André, Mats
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Graham, Daniel B.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Khotyaintsev, Yuri V.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Vaivads, Andris
    KTH Royal Inst Technol, Stockholm, Sweden.
    Chappell, Charles R.
    Vanderbilt Univ, Dept Phys & Astron, Vanderbilt Dyer Observ, Nashville, TN 37235 USA.
    Dargent, Jeremy
    Univ Pisa, Phys Dept Enrico Fermi, Pisa, Italy.
    Fuselier, Stephen A.
    Southwest Res Inst, San Antonio, TX USA;Univ Texas San Antonio, Dept Phys & Astron, San Antonio, TX USA.
    Haaland, Stein
    Max Planck Inst Solar Syst Res, Gottingen, Germany;Univ Bergen, Birkeland Ctr Space Sci, Bergen, Norway.
    Lavraud, Benoit
    Univ Toulouse, Inst Rech Astrophys & Planetol, CNRS, UPS,CNES, Toulouse, France.
    Li, Wenya
    Chinese Acad Sci, Natl Space Sci Ctr, State Key Lab Space Weather, Beijing, Peoples R China.
    Tenfjord, Paul
    Univ Bergen, Birkeland Ctr Space Sci, Bergen, Norway.
    Toledo-Redondo, Sergio
    Univ Toulouse, Inst Rech Astrophys & Planetol, CNRS, UPS,CNES, Toulouse, France.
    Vines, Sarah K.
    Johns Hopkins Univ, Appl Phys Lab, Laurel, MD USA.
    MMS Observations of Multiscale Hall Physics in the Magnetotail2019Ingår i: Geophysical Research Letters, ISSN 0094-8276, E-ISSN 1944-8007, Vol. 46, nr 17-18, s. 10230-10239Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We present Magnetospheric Multiscale mission (MMS) observations of Hall physics in the magnetotail, which compared to dayside Hall physics is a relatively unexplored topic. The plasma consists of electrons, moderately cold ions (T similar to 1.5 keV) and hot ions (T similar to 20 keV). MMS can differentiate between the cold ion demagnetization region and hot ion demagnetization regions, which suggests that MMS was observing multiscale Hall physics. The observed Hall electric field is compared with a generalized Ohm's law, accounting for multiple ion populations. The cold ion population, despite its relatively high initial temperature, has a significant impact on the Hall electric field. These results show that multiscale Hall physics is relevant over a much larger temperature range than previously observed and is relevant for the whole magnetosphere as well as for other astrophysical plasma.

  • 21.
    Alm, Love
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    André, Mats
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Vaivads, Andris
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Khotyaintsev, Yuri V.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Torbert, R. B.
    Univ New Hampshire, Ctr Space Sci, Durham, NH 03824 USA;Southwest Res Inst, San Antonio, TX USA.
    Burch, J. L.
    Southwest Res Inst, San Antonio, TX USA.
    Ergun, R. E.
    Univ Colorado, Atmospher & Space Phys Lab, Campus Box 392, Boulder, CO 80309 USA.
    Lindqvist, P. -A
    Russell, C. T.
    Univ Calif Los Angeles, IGPP EPSS, Los Angeles, CA USA.
    Giles, B. L.
    NASA, Goddard Space Flight Ctr, Greenbelt, MD USA.
    Mauk, B. H.
    Johns Hopkins Univ, Appl Phys Lab, Laurel, MD USA.
    Magnetotail Hall Physics in the Presence of Cold Ions2018Ingår i: Geophysical Research Letters, ISSN 0094-8276, E-ISSN 1944-8007, Vol. 45, nr 20, s. 10941-10950Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We present the first in situ observation of cold ionospheric ions modifying the Hall physics of magnetotail reconnection. While in the tail lobe, Magnetospheric Multiscale mission observed cold (tens of eV) E x B drifting ions. As Magnetospheric Multiscale mission crossed the separatrix of a reconnection exhaust, both cold lobe ions and hot (keV) ions were observed. During the closest approach of the neutral sheet, the cold ions accounted for similar to 30% of the total ion density. Approximately 65% of the initial cold ions remained cold enough to stay magnetized. The Hall electric field was mainly supported by the j x B term of the generalized Ohm's law, with significant contributions from the del center dot P-e and v(c) x B terms. The results show that cold ions can play an important role in modifying the Hall physics of magnetic reconnection even well inside the plasma sheet. This indicates that modeling magnetic reconnection may benefit from including multiscale Hall physics. Plain Language Summary Cold ions have the potential of changing the fundamental physics behind magnetic reconnection. Here we present the first direct observation of this process in action in the magnetotail. Cold ions from the tail lobes were able to remain cold even deep inside the much hotter plasma sheet. Even though the cold ions only accounted for similar to 30% of the total ions, they had a significant impact on the electric fields near the reconnection region.

  • 22.
    Alqeeq, S. W.
    et al.
    Univ Paris Saclay, Inst Polytech Paris, UMR7648, Lab Phys Plasmas LPP,CNRS,Sorbonne Univ,Observ Par, Paris, France..
    Le Contel, O.
    Univ Paris Saclay, Inst Polytech Paris, UMR7648, Lab Phys Plasmas LPP,CNRS,Sorbonne Univ,Observ Par, Paris, France..
    Canu, P.
    Univ Paris Saclay, Inst Polytech Paris, UMR7648, Lab Phys Plasmas LPP,CNRS,Sorbonne Univ,Observ Par, Paris, France..
    Retino, A.
    Univ Paris Saclay, Inst Polytech Paris, UMR7648, Lab Phys Plasmas LPP,CNRS,Sorbonne Univ,Observ Par, Paris, France..
    Chust, T.
    Univ Paris Saclay, Inst Polytech Paris, UMR7648, Lab Phys Plasmas LPP,CNRS,Sorbonne Univ,Observ Par, Paris, France..
    Mirioni, L.
    Univ Paris Saclay, Inst Polytech Paris, UMR7648, Lab Phys Plasmas LPP,CNRS,Sorbonne Univ,Observ Par, Paris, France..
    Chuvatin, A.
    Univ Paris Saclay, Inst Polytech Paris, UMR7648, Lab Phys Plasmas LPP,CNRS,Sorbonne Univ,Observ Par, Paris, France..
    Nakamura, R.
    Austrian Acad Sci, Space Res Inst, Graz, Austria..
    Ahmadi, N.
    Univ Colorado, Lab Atmospher & Space Phys, Boulder, CO USA..
    Wilder, F. D.
    Univ Texas Arlington, Dept Phys, Arlington, TX USA..
    Gershman, D. J.
    NASA, Goddard Space Flight Ctr, Greenbelt, MD USA..
    Khotyaintsev, Yuri V.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Lindqvist, P. -A
    Ergun, R. E.
    Univ Colorado, Lab Atmospher & Space Phys, Boulder, CO USA..
    Burch, J. L.
    Southwest Res Inst, San Antonio, TX USA.;Univ Texas San Antonio, San Antonio, TX USA..
    Torbert, R. B.
    Univ New Hampshire, Space Sci Ctr, Durham, NH USA.;Univ New Hampshire, Dept Phys, Durham, NH USA..
    Fuselier, S. A.
    Southwest Res Inst, San Antonio, TX USA.;Univ Texas San Antonio, San Antonio, TX USA..
    Russell, C. T.
    Univ Calif Los Angeles, Dept Earth Planetary & Space Sci, Los Angeles, CA USA..
    Wei, H. Y.
    Univ Calif Los Angeles, Dept Earth Planetary & Space Sci, Los Angeles, CA USA..
    Strangeway, R. J.
    Univ Calif Los Angeles, Dept Earth Planetary & Space Sci, Los Angeles, CA USA..
    Bromund, K. R.
    NASA, Goddard Space Flight Ctr, Greenbelt, MD USA..
    Fischer, D.
    Austrian Acad Sci, Space Res Inst, Graz, Austria..
    Giles, B. L.
    NASA, Goddard Space Flight Ctr, Greenbelt, MD USA..
    Saito, Y.
    Inst Space & Astronaut Sci, Sagamihara, Japan..
    Two Classes of Equatorial Magnetotail Dipolarization Fronts Observed by Magnetospheric Multiscale Mission: A Statistical Overview2023Ingår i: Journal of Geophysical Research - Space Physics, ISSN 2169-9380, E-ISSN 2169-9402, Vol. 128, nr 10, artikel-id e2023JA031738Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We carried out a statistical study of equatorial dipolarization fronts (DFs) detected by the Magnetospheric Multiscale mission during the full 2017 Earth's magnetotail season. We found that two DF classes are distinguished: class I (74.4%) corresponds to the standard DF properties and energy dissipation and a new class II (25.6%). This new class includes the six DF discussed in Alqeeq et al. (2022, ) and corresponds to a bump of the magnetic field associated with a minimum in the ion and electron pressures and a reversal of the energy conversion process. The possible origin of this second class is discussed. Both DF classes show that the energy conversion process in the spacecraft frame is driven by the diamagnetic current dominated by the ion pressure gradient. In the fluid frame, it is driven by the electron pressure gradient. In addition, we have shown that the energy conversion processes are not homogeneous at the electron scale mostly due to the variations of the electric fields for both DF classes.

  • 23.
    Alqeeq, S. W.
    et al.
    Univ Paris Saclay, Inst Polytech Paris, Lab Phys Plasmas LPP,CNRS, Sorbonne Univ,Ecole Polytech,Observ Paris,UMR7648, F-75005 Paris, France..
    Le Contel, O.
    Univ Paris Saclay, Inst Polytech Paris, Lab Phys Plasmas LPP,CNRS, Sorbonne Univ,Ecole Polytech,Observ Paris,UMR7648, F-75005 Paris, France..
    Canu, P.
    Univ Paris Saclay, Inst Polytech Paris, Lab Phys Plasmas LPP,CNRS, Sorbonne Univ,Ecole Polytech,Observ Paris,UMR7648, F-75005 Paris, France..
    Retino, A.
    Univ Paris Saclay, Inst Polytech Paris, Lab Phys Plasmas LPP,CNRS, Sorbonne Univ,Ecole Polytech,Observ Paris,UMR7648, F-75005 Paris, France..
    Chust, T.
    Univ Paris Saclay, Inst Polytech Paris, Lab Phys Plasmas LPP,CNRS, Sorbonne Univ,Ecole Polytech,Observ Paris,UMR7648, F-75005 Paris, France..
    Mirioni, L.
    Univ Paris Saclay, Inst Polytech Paris, Lab Phys Plasmas LPP,CNRS, Sorbonne Univ,Ecole Polytech,Observ Paris,UMR7648, F-75005 Paris, France..
    Richard, Louis
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Rymd- och plasmafysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Ait-Si-Ahmed, Y.
    Univ Paris Saclay, Inst Polytech Paris, Lab Phys Plasmas LPP,CNRS, Sorbonne Univ,Ecole Polytech,Observ Paris,UMR7648, F-75005 Paris, France..
    Alexandrova, A.
    Univ Paris Saclay, Inst Polytech Paris, Lab Phys Plasmas LPP,CNRS, Sorbonne Univ,Ecole Polytech,Observ Paris,UMR7648, F-75005 Paris, France..
    Chuvatin, A.
    Univ Paris Saclay, Inst Polytech Paris, Lab Phys Plasmas LPP,CNRS, Sorbonne Univ,Ecole Polytech,Observ Paris,UMR7648, F-75005 Paris, France..
    Ahmadi, N.
    Univ Colorado, Lab Atmospher & Space Phys, Boulder, CO 80303 USA..
    Baraka, S. M.
    Hampton Univ, NIA, Hampton, VA 23666 USA..
    Nakamura, R.
    Wilder, F. D.
    Austrian Acad Sci, Space Res Inst, A-8042 Graz, Austria.;Univ Texas Arlington, Phys Fac, Arlington, TX 76019 USA..
    Gershman, D. J.
    NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA..
    Lindqvist, P. A.
    Royal Inst Technol, S-11428 Stockholm, Sweden..
    Khotyaintsev, Yuri V.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Ergun, R. E.
    Univ Colorado, Lab Atmospher & Space Phys, Boulder, CO 80303 USA..
    Burch, J. L.
    Southwest Res Inst, San Antonio, TX 78238 USA..
    Torbert, R. B.
    Univ New Hampshire, Space Sci Ctr, Durham, NH 03824 USA.;Univ New Hampshire, Dept Phys, Durham, NH 03824 USA..
    Russell, C. T.
    Univ Calif Los Angeles, Dept Earth Planetary & Space Sci, Los Angeles, CA 90095 USA..
    Magnes, W.
    Hampton Univ, NIA, Hampton, VA 23666 USA..
    Strangeway, R. J.
    Univ Calif Los Angeles, Dept Earth Planetary & Space Sci, Los Angeles, CA 90095 USA..
    Bromund, K. R.
    NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA..
    Wei, H.
    Univ New Hampshire, Dept Phys, Durham, NH 03824 USA..
    Plaschke, F.
    Austrian Acad Sci, Space Res Inst, A-8042 Graz, Austria..
    Anderson, B. J.
    Johns Hopkins Univ, Appl Phys Lab, Johns Hopkins Rd, Laurel, MD 20723 USA..
    Giles, B. L.
    NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA..
    Fuselier, S. A.
    Southwest Res Inst, San Antonio, TX 78238 USA..
    Saito, Y.
    Inst Space & Astronaut Sci, Sagamihara, Kanagawa 2525210, Japan..
    Lavraud, B.
    Univ Paul Sabatier, CNRS, UMR5277, Inst Rech Astrophys & Planetol IRAP, F-31400 Toulouse, France..
    Investigation of the homogeneity of energy conversion processes at dipolarization fronts from MMS measurements2022Ingår i: Physics of Plasmas, ISSN 1070-664X, E-ISSN 1089-7674, Vol. 29, nr 1, artikel-id 012906Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We report on six dipolarization fronts (DFs) embedded in fast earthward flows detected by the Magnetospheric Multiscale mission during a substorm event on 23 July 2017. We analyzed Ohm's law for each event and found that ions are mostly decoupled from the magnetic field by Hall fields. However, the electron pressure gradient term is also contributing to the ion decoupling and likely responsible for an electron decoupling at DF. We also analyzed the energy conversion process and found that the energy in the spacecraft frame is transferred from the electromagnetic field to the plasma (J & BULL; E > 0) ahead or at the DF, whereas it is the opposite (J & BULL; E < 0) behind the front. This reversal is mainly due to a local reversal of the cross-tail current indicating a substructure of the DF. In the fluid frame, we found that the energy is mostly transferred from the plasma to the electromagnetic field (J & BULL; E & PRIME; < 0) and should contribute to the deceleration of the fast flow. However, we show that the energy conversion process is not homogeneous at the electron scales due to electric field fluctuations likely related to lower-hybrid drift waves. Our results suggest that the role of DF in the global energy cycle of the magnetosphere still deserves more investigation. In particular, statistical studies on DF are required to be carried out with caution due to these electron scale substructures.

  • 24. Andersson, Ludvig
    et al.
    Rasouli, Karwan
    Modeling fuel ion orbits during sawtooth instabilities in fusion plasmas2017Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    An important part of the fusion research program is to understand and control the large number of plasma instabilities that a fusion plasma can exhibit. One such instability is known as the “sawtooth” instability, which is a perturbation in the plasma electric and magnetic fields that manifests itself as periodic relaxations of the temperature and density in the plasma center.

    The aim of this project was to investigate how the fuel ions in a fusion plasma react to the sawtooth instability.

    We were able to implement a model of the plasma electromagnetic field during a sawtooth relaxation into an existing code that computes the orbits of the fuel ions in the tokamak magnetic field. To this end, it was necessary to modify the orbit code to allow for non-zero electric fields, and for time-varying fields. In order to validate the new additions to the code, we compared simulated results to analytical ones.

    The model of the sawtooth electromagnetic fields required for our simulations was set up within a different student project. However, due to unforeseen complications, only the magnetic (not the electric) field contribution was available to us during our project, but once the electric field is available it is straightforward to include in our code.

    Our simulations did not exhibit any noticeable perturbation to the particle orbit during a sawtooth crash. However, before the electric field contribution is included it is not possible to draw any physics conclusions from these results. Our code could also be used as a foundation for future projects since it is possible (with further implementations to the existing code) to simulate how the spatial profile of the neutron emission is expected to vary during the sawtooth. These simulations can be compared against experimental measurements of the neutron emission profile in order to investigate the accuracy of the sawtooth model under consideration.

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  • 25.
    Andreasson, Jakob
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär biofysik.
    Timneanu, Nicusor
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär biofysik.
    Iwan, Bianca
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär biofysik.
    Hantke, Max
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär biofysik.
    Rath, Asawari
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär biofysik.
    Ekeberg, Tomas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär biofysik.
    Maia, Filipe R. N. C.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär biofysik.
    Barty, Anton
    Chapman, Henry N.
    Bielecki, Johan
    Abergel, C.
    Seltzer, V.
    Claverie, J.-M.
    Svenda, M.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär biofysik.
    Hajdu, Janos
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär biofysik.
    Time of Flight Mass Spectrometry to Monitor Sample Expansion in Flash Diffraction Studies on Single Virus ParticlesManuskript (preprint) (Övrigt vetenskapligt)
  • 26.
    Andres, N.
    et al.
    Univ Paris Sud, Sorbonne Univ, Lab Phys Plasmas, CNRS,Ecole Polytech,Observ Paris, F-91128 Palaiseau, France.
    Sahraoui, F.
    Univ Paris Sud, Sorbonne Univ, Lab Phys Plasmas, CNRS,Ecole Polytech,Observ Paris, F-91128 Palaiseau, France.
    Galtier, S.
    Univ Paris Sud, Sorbonne Univ, Lab Phys Plasmas, CNRS,Ecole Polytech,Observ Paris, F-91128 Palaiseau, France;Univ Paris Saclay, Univ Paris Sud, Paris, France.
    Hadid, Lina Z
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Dmitruk, P.
    UBA, CONICET, Inst Fis Buenos Aires, Ciudad Univ, RA-1428 Buenos Aires, DF, Argentina.
    Mininni, P. D.
    Univ Buenos Aires, Fac Ciencias Exactas & Nat, Dept Fis, Ciudad Univ, RA-1428 Buenos Aires, DF, Argentina.
    Energy cascade rate in isothermal compressible magnetohydrodynamic turbulence2018Ingår i: Journal of Plasma Physics, ISSN 0022-3778, E-ISSN 1469-7807, Vol. 84, nr 4, artikel-id 905840404Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Three-dimensional direct numerical simulations are used to study the energy cascade rate in isothermal compressible magnetohydrodynamic turbulence. Our analysis is guided by a two-point exact law derived recently for this problem in which flux, source, hybrid and mixed terms are present. The relative importance of each term is studied for different initial subsonic Mach numbers M-S and different magnetic guide fields B-0. The dominant contribution to the energy cascade rate comes from the compressible flux, which depends weakly on the magnetic guide field B-0, unlike the other terms whose moduli increase significantly with M s and B-0. In particular, for strong B-0 the source and hybrid terms are dominant at small scales with almost the same amplitude but with a different sign. A statistical analysis undertaken with an isotropic decomposition based on the SO(3) rotation group is shown to generate spurious results in the presence of B-0, when compared with an axisymmetric decomposition better suited to the geometry of the problem. Our numerical results are compared with previous analyses made with in situ measurements in the solar wind and the terrestrial magnetosheath.

  • 27.
    Andrews, David J.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Andersson, L.
    Lab Atmospher & Space Phys, Boulder, CO USA..
    Delory, G. T.
    Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA..
    Ergun, R. E.
    Lab Atmospher & Space Phys, Boulder, CO USA..
    Eriksson, Anders I.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Fowler, C. M.
    Lab Atmospher & Space Phys, Boulder, CO USA..
    McEnulty, T.
    Lab Atmospher & Space Phys, Boulder, CO USA..
    Morooka, M. W.
    Lab Atmospher & Space Phys, Boulder, CO USA..
    Weber, T.
    Lab Atmospher & Space Phys, Boulder, CO USA..
    Jakosky, B. M.
    Lab Atmospher & Space Phys, Boulder, CO USA..
    Ionospheric plasma density variations observed at Mars by MAVEN/LPW2015Ingår i: Geophysical Research Letters, ISSN 0094-8276, E-ISSN 1944-8007, Vol. 42, nr 21, s. 8862-8869Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We report on initial observations made by the Langmuir Probe and Waves relaxation sounding experiment on board the NASA Mars Atmosphere and Volatile EvolutioN (MAVEN) mission. These measurements yield the ionospheric thermal plasma density, and we use these data here for an initial survey of its variability. Studying orbit-to-orbit variations, we show that the relative variability of the ionospheric plasma density is lowest at low altitudes near the photochemical peak, steadily increases toward higher altitudes and sharply increases as the spacecraft crosses the terminator and moves into the nightside. Finally, despite the small volume of data currently available, we show that a clear signature of the influence of crustal magnetic fields on the thermal plasma density fluctuations is visible. Such results are consistent with previously reported remote measurements made at higher altitudes, but crucially, here we sample a new span of altitudes between similar to 130 and similar to 300 km using in situ techniques.

  • 28.
    Andrews, David J.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    André, Mats
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Opgenoorth, Hermann J.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Edberg, Niklas J. T.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Dieval, C.
    Duru, F.
    Gurnett, D. A.
    Morgan, D.
    Witasse, O.
    Oblique reflections in the Mars Express MARSIS data set: Stable density structures in the Martian ionosphere2014Ingår i: Journal of Geophysical Research-Space Physics, ISSN 2169-9380, Vol. 119, nr 5, s. 3944-3960Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) onboard the European Space Agency's Mars Express (MEX) spacecraft routinely detects evidence of localized plasma density structures in the Martian dayside ionosphere. Such structures, likely taking the form of spatially extended elevations in the plasma density at a given altitude, give rise to oblique reflections in the Active Ionospheric Sounder data. These structures are likely related to the highly varied Martian crustal magnetic field. In this study we use the polar orbit of MEX to investigate the repeatability of the ionospheric structures producing these anomalous reflections, examining data taken in sequences of multiple orbits which pass over the same regions of the Martian surface under similar solar illuminations, within intervals lasting tens of days. Presenting three such examples, or case studies, we show for the first time that these oblique reflections are often incredibly stable, indicating that the underlying ionospheric structures are reliably reformed in the same locations and with qualitatively similar parameters. The visibility, or lack thereof, of a given oblique reflection on a single orbit can generally be attributed to variations in the crustal field within the ionosphere along the spacecraft trajectory. We show that, within these examples, oblique reflections are generally detected whenever the spacecraft passes over regions of intense near-radial crustal magnetic fields (i.e., with a cusp-like configuration). The apparent stability of these structures is an important feature that must be accounted for in models of their origin.

  • 29.
    Andrews, David J.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Cowley, S. W. H.
    Univ Leicester, Dept Phys & Astron, Leicester, Leics, England.
    Provan, G.
    Univ Leicester, Dept Phys & Astron, Leicester, Leics, England.
    Hunt, G. J.
    Imperial Coll London, Blackett Lab, London, England.
    Hadid, Lina Z
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Morooka, Michiko
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Wahlund, Jan-Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    The Structure of Planetary Period Oscillations in Saturn's Equatorial Magnetosphere: Results From the Cassini Mission2019Ingår i: Journal of Geophysical Research - Space Physics, ISSN 2169-9380, E-ISSN 2169-9402, Vol. 124, nr 11, s. 8361-8395Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Saturn's magnetospheric magnetic field, planetary radio emissions, plasma populations, and magnetospheric structure are all known to be modulated at periods close to the assumed rotation period of the planetary interior. These oscillations are readily apparent despite the high degree of axisymmetry in the internally produced magnetic field of the planet and have different rotation periods in the northern and southern hemispheres. In this paper we study the spatial structure of (near-)planetary period magnetic field oscillations in Saturn's equatorial magnetosphere. Extending previous analyses of these phenomena, we include all suitable data from the entire Cassini mission during its orbital tour of the planet so as to be able to quantify both the amplitude and phase of these field oscillations throughout Saturn's equatorial plane, to distances of 30 planetary radii. We study the structure of these field oscillations in view of both independently rotating northern and southern systems, finding spatial variations in both magnetic fields and inferred currents flowing north-south that are common to both systems. With the greatly expanded coverage of the equatorial plane achieved during the latter years of the mission, we are able to present a complete survey of dawn-dusk and day-night asymmetries in the structure of the oscillating fields and currents. We show that the general structure of the rotating currents is simpler than previously reported and that the relatively enhanced nightside equatorial fields and currents are due in part to related periodic vertical motion of Saturn's magnetotail current sheet.

  • 30.
    Andrews, David J.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Opgenoorth, Hermann J.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Leyser, Thomas B.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Buchert, Stephan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Edberg, Niklas J. T.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Morgan, D. D.
    Univ Iowa, Dept Phys & Astron, Iowa City, IA USA.
    Gurnett, D. A.
    Univ Iowa, Dept Phys & Astron, Iowa City, IA USA.
    Kopf, A. J.
    Univ Iowa, Dept Phys & Astron, Iowa City, IA USA.
    Fallows, K.
    Boston Univ, Ctr Space Phys, Boston, MA USA.
    Withers, P.
    Boston Univ, Ctr Space Phys, Boston, MA USA; Boston Univ, Dept Astron, Commonwealth Ave, Boston, MA USA.
    MARSIS Observations of Field-Aligned Irregularities and Ducted Radio Propagation in the Martian Ionosphere2018Ingår i: Journal of Geophysical Research - Space Physics, ISSN 2169-9380, E-ISSN 2169-9402, Vol. 123, nr 8, s. 6251-6263Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Knowledge of Mars's ionosphere has been significantly advanced in recent years by observations from Mars Express and lately Mars Atmosphere and Volatile EvolutioN. A topic of particular interest are the interactions between the planet's ionospheric plasma and its highly structured crustal magnetic fields and how these lead to the redistribution of plasma and affect the propagation of radio waves in the system. In this paper, we elucidate a possible relationship between two anomalous radar signatures previously reported in observations from the Mars Advanced Radar for Subsurface and Ionospheric Sounding instrument on Mars Express. Relatively uncommon observations of localized, extreme increases in the ionospheric peak density in regions of radial (cusp-like) magnetic fields and spread echo radar signatures are shown to be coincident with ducting of the same radar pulses at higher altitudes on the same field lines. We suggest that these two observations are both caused by a high electric field (perpendicular to B) having distinctly different effects in two altitude regimes. At lower altitudes, where ions are demagnetized and electrons magnetized, and recombination dominantes, a high electric field causes irregularities, plasma turbulence, electron heating, slower recombination, and ultimately enhanced plasma densities. However, at higher altitudes, where both ions and electrons are magnetized and atomic oxygen ions cannot recombine directly, the high electric field instead causes frictional heating, a faster production of molecular ions by charge exchange, and so a density decrease. The latter enables ducting of radar pulses on closed field lines, in an analogous fashion to interhemispheric ducting in the Earth's ionosphere.

  • 31.
    Andriopoulou, M.
    et al.
    Austrian Acad Sci, Space Res Inst, A-8010 Graz, Austria..
    Nakamura, R.
    Austrian Acad Sci, Space Res Inst, A-8010 Graz, Austria..
    Torkar, K.
    Austrian Acad Sci, Space Res Inst, A-8010 Graz, Austria..
    Baumjohann, W.
    Austrian Acad Sci, Space Res Inst, A-8010 Graz, Austria..
    Torbert, R. B.
    Univ New Hampshire, Inst Study Earth Oceans & Space, Durham, NH 03824 USA..
    Lindqvist, P. -A
    Khotyaintsev, Yuri V.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Dorelli, J.
    NASA, Goddard Space Flight Ctr, Greenbelt, MD USA..
    Burch, J. L.
    SW Res Inst, San Antonio, TX USA..
    Russell, C. T.
    Univ Calif Los Angeles, Dept Earth Planetary & Space Sci, Los Angeles, CA USA..
    Study of the spacecraft potential under active control and plasma density estimates during the MMS commissioning phase2016Ingår i: Geophysical Research Letters, ISSN 0094-8276, E-ISSN 1944-8007, Vol. 43, nr 10, s. 4858-4864Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Each spacecraft of the recently launched magnetospheric multiscale MMS mission is equipped with Active Spacecraft Potential Control (ASPOC) instruments, which control the spacecraft potential in order to reduce spacecraft charging effects. ASPOC typically reduces the spacecraft potential to a few volts. On several occasions during the commissioning phase of the mission, the ASPOC instruments were operating only on one spacecraft at a time. Taking advantage of such intervals, we derive photoelectron curves and also perform reconstructions of the uncontrolled spacecraft potential for the spacecraft with active control and estimate the electron plasma density during those periods. We also establish the criteria under which our methods can be applied.

  • 32.
    Andriopoulou, Maria
    et al.
    Austrian Acad Sci, Space Res Inst, Graz, Austria.
    Nakamura, Rumi
    Austrian Acad Sci, Space Res Inst, Graz, Austria.
    Wellenzohn, Simon
    Karl Franzens Univ Graz, Inst Geophys Astrophys & Meteorol, Graz, Austria.
    Torkar, Klaus
    Austrian Acad Sci, Space Res Inst, Graz, Austria.
    Baumjohann, Wolfgang
    Austrian Acad Sci, Space Res Inst, Graz, Austria.
    Torbert, R. B.
    Univ New Hampshire, Dept Phys, Durham, NH 03824 USA;Univ New Hampshire, Ctr Space Sci, Durham, NH 03824 USA.
    Lindqvist, Per-Arne
    KTH Royal Inst Technol, Dept Space & Plasma Phys, Stockholm, Sweden.
    Khotyaintsev, Yuri V.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Dorelli, John
    NASA, Goddard Space Flight Ctr, Greenbelt, MD USA.
    Burch, James L.
    Southwest Res Inst, San Antonio, TX USA.
    Plasma Density Estimates From Spacecraft Potential Using MMS Observations in the Dayside Magnetosphere2018Ingår i: Journal of Geophysical Research - Space Physics, ISSN 2169-9380, E-ISSN 2169-9402, Vol. 123, nr 4, s. 2620-2629Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Using spacecraft potential observations with and without active spacecraft potential control (on/off) from the Magnetospheric Multiscale (MMS) mission, we estimate the average photoelectron emission as well as derive the plasma density information from spacecraft potential variations and active spacecraft potential control ion current. Such estimates are of particular importance especially during periods when the plasma instruments are not in operation and also when electron density observations with higher time resolution than the ones available from particle detectors are necessary. We compare the average photoelectron emission of different spacecraft and discuss their differences. We examine several time intervals when we performed our density estimations in order to understand the strengths and weaknesses of our data set. We finally compare our derived density estimates with the plasma density observations provided by plasma detectors onboard MMS, whenever available, and discuss the overall results. The estimated electron densities should only be used as a proxy of the electron density, complimentary to the plasma moments derived by plasma detectors, especially when the latter are turned off or when higher time resolution observations are required. While the derived data set can often provide valuable information about the plasma environment, the actual values may often be very far from the actual plasma density values and should therefore be used with caution.

  • 33.
    Andrushchenko Zh.N., Pavlenko V.P.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för astronomi och rymdfysik.
    Turbulent generation of large scale flows and nonlinear dynamics of flute modes2002Ingår i: Physics of Plasmas, Vol. 9, s. 4512-Artikel i tidskrift (Refereegranskat)
  • 34.
    Andrushchenko Zh.N., Pavlenko V.P., Schoepf K.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för astronomi och rymdfysik.
    Theory of zonal flow generation by flute type turbulence2002Ingår i: Physica Scripta, Vol. 66, s. 326-Artikel i tidskrift (Refereegranskat)
  • 35.
    André, Mats
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Previously hidden low-energy ions: a better map of near-Earth space and the terrestrial mass balance2015Ingår i: Physica Scripta, ISSN 0031-8949, E-ISSN 1402-4896, Vol. 90, nr 12, artikel-id 128005Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This is a review of the mass balance of planet Earth, intended also for scientists not usually working with space physics or geophysics. The discussion includes both outflow of ions and neutrals from the ionosphere and upper atmosphere, and the inflow of meteoroids and larger objects. The focus is on ions with energies less than tens of eV originating from the ionosphere. Positive low-energy ions are complicated to detect onboard sunlit spacecraft at higher altitudes, which often become positively charged to several tens of volts. We have invented a technique to observe low-energy ions based on the detection of the wake behind a charged spacecraft in a supersonic ion flow. We find that low-energy ions usually dominate the ion density and the outward flux in large volumes in the magnetosphere. The global outflow is of the order of 10(26) ions s(-1). This is a significant fraction of the total number outflow of particles from Earth, and changes plasma processes in near-Earth space. We compare order of magnitude estimates of the mass outflow and inflow for planet Earth and find that they are similar, at around 1 kg s(-1) (30 000 ton yr(-1)). We briefly discuss atmospheric and ionospheric outflow from other planets and the connection to evolution of extraterrestrial life.

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  • 36.
    André, Mats
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Eriksson, Anders, I
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Khotyaintsev, Yuri V.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Toledo-Redondo, Sergio
    Univ Murcia, Dept Electromagnetism & Elect, Murcia, Spain..
    The Spacecraft Wake: Interference With Electric Field Observations and a Possibility to Detect Cold Ions2021Ingår i: Journal of Geophysical Research - Space Physics, ISSN 2169-9380, E-ISSN 2169-9402, Vol. 126, nr 9, artikel-id e2021JA029493Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Wakes behind spacecraft caused by supersonic drifting positive ions are common in plasmas and disturb in situ measurements. We review the impact of wakes on observations by the Electric Field and Wave double-probe instruments on the Cluster satellites. In the solar wind, the equivalent spacecraft charging is small compared to the ion drift energy and the wake effects are caused by the spacecraft body and can be compensated for. We present statistics of the direction, width, and electrostatic potential of wakes, and we compare with an analytical model. In the low-density magnetospheric lobes, the equivalent positive spacecraft charging is large compared to the ion drift energy and an enhanced wake forms. In this case observations of the geophysical electric field with the double-probe technique becomes extremely challenging. Rather, the wake can be used to estimate the flux of cold (eV) positive ions. For an intermediate range of parameters, when the equivalent charging of the spacecraft is similar to the drift energy of the ions, also the charged wire booms of a double-probe instrument must be taken into account. We discuss an example of these effects from the MMS spacecraft near the magnetopause. We find that many observed wake characteristics provide information that can be used for scientific studies. An important example is the enhanced wakes used to estimate the outflow of ionospheric origin in the magnetospheric lobes to about 10 26 cold (eV) ions/s, constituting a large fraction of the mass outflow from planet Earth.

  • 37.
    André, Mats
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Odelstad, Elias
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Rymd- och plasmafysik.
    Graham, Daniel B.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Eriksson, Anders I.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Karlsson, T.
    KTH Royal Inst Technol, Sch Elect Engn, Dept Space & Plasma Phys, Stockholm, Sweden.
    Wieser, G. Stenberg
    Swedish Inst Space Phys, Kiruna, Sweden.
    Vigren, Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Norgren, Cecilia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Rymd- och plasmafysik.
    Johansson, Fredrik L.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Henri, P.
    Lab Phys & Chim Environm & Espace, Orleans, France.
    Rubin, M.
    Univ Bern, Phys Inst, Bern, Switzerland.
    Richter, I.
    TU Braunschweig, Inst Geophys & Extraterr Phys, Braunschweig, Germany.
    Lower hybrid waves at comet 67P/Churyumov-Gerasimenko2017Ingår i: Monthly notices of the Royal Astronomical Society, ISSN 0035-8711, E-ISSN 1365-2966, Vol. 469, s. S29-S38Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We investigate the generation of waves in the lower hybrid frequency range by density gradients in the near plasma environment of comet 67P/Churyumov-Gerasimenko. When the plasma is dominated by water ions from the comet, a situation with magnetized electrons and unmagnetized ions is favourable for the generation of lower hybrid waves. These waves can transfer energy between ions and electrons and reshape the plasma environment of the comet. We consider cometocentric distances out to a few hundred km. We find that when the electron motion is not significantly interrupted by collisions with neutrals, large average gradients within tens of km of the comet, as well as often observed local large density gradients at larger distances, are often likely to be favourable for the generation of lower hybrid waves. Overall, we find that waves in the lower hybrid frequency range are likely to be common in the near plasma environment.

  • 38. Angioni, C.
    et al.
    Andersson Sundén, Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Asp, E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Binda, Federico
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Cecconello, Marco
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Conroy, Sean
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Dzysiuk, Nataliia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Ericsson, Göran
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Eriksson, Jacob
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Hellesen, Carl
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Hjalmarsson, Anders
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Possnert, Göran
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Sjöstrand, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Skiba, Mateusz
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Weiszflog, Matthias
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Zychor, I.
    Gyrokinetic study of turbulent convection of heavy impurities in tokamak plasmas at comparable ion and electron heat fluxes2017Ingår i: Nuclear Fusion, ISSN 0029-5515, E-ISSN 1741-4326, Vol. 57, nr 2, artikel-id 022009Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In tokamaks, the role of turbulent transport of heavy impurities, relative to that of neoclassical transport, increases with increasing size of the plasma, as clarified by means of general scalings, which use the ITER standard scenario parameters as reference, and by actual results from a selection of discharges from ASDEX Upgrade and JET. This motivates the theoretical investigation of the properties of the turbulent convection of heavy impurities by nonlinear gyrokinetic simulations in the experimentally relevant conditions of comparable ion and electron heat fluxes. These conditions also correspond to an intermediate regime between dominant ion temperature gradient turbulence and trapped electron mode turbulence. At moderate plasma toroidal rotation, the turbulent convection of heavy impurities, computed with nonlinear gyrokinetic simulations, is found to be directed outward, in contrast to that obtained by quasi-linear calculations based on the most unstable linear mode, which is directed inward. In this mixed turbulence regime, with comparable electron and ion heat fluxes, the nonlinear results of the impurity transport can be explained by the coexistence of both ion temperature gradient and trapped electron modes in the turbulent state, both contributing to the turbulent convection and diffusion of the impurity. The impact of toroidal rotation on the turbulent convection is also clarified.

  • 39. Angioni, C.
    et al.
    Andersson Sundén, Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Binda, F.
    Cecconello, Marco
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Conroy, Sean
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Dzysiuk, N.
    Ericsson, Göran
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Eriksson, Jacob
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Hellesen, C.
    Hjalmarsson, Anders
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Possnert, Göran
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Högenergifysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Sjöstrand, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Skiba, M.
    Weiszflog, Matthias
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Zychor, I.
    Dependence of the turbulent particle flux on hydrogen isotopes induced by collisionality2018Ingår i: Physics of fluids, ISSN 1070-6631, E-ISSN 1089-7666, Vol. 25, nr 8, artikel-id 082517Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The impact of the change of the mass of hydrogen isotopes on the turbulent particle flux is studied. The trapped electron component of the turbulent particle convection induced by collisionality, which is outward in ion temperature gradient turbulence, increases with decreasing thermal velocity of the isotope. Thereby, the lighter is the isotope, the stronger is the turbulent pinch, and the larger is the predicted density gradient at the null of the particle flux. The passing particle component of the flux increases with decreasing mass of the isotope and can also affect the predicted density gradient. This effect is however subdominant for usual core plasma parameters. The analytical results are confirmed by means of both quasi-linear and nonlinear gyrokinetic simulations, and an estimate of the difference in local density gradient produced by this effect as a function of collisionality has been obtained for typical plasma parameters at mid-radius. Analysis of currently available experimental data from the JET and the ASDEX Upgrade tokamaks does not show any clear and general evidence of inconsistency with this theoretically predicted effect outside the errorbars and also allows the identification of cases providing weak evidence of qualitative consistency.

  • 40.
    Angioni, C.
    et al.
    Max Planck Inst Plasma Phys, D-85748 Garching, Germany;Max Planck Inst Plasma Phys, D-85748 Garching, Germany.
    Andersson Sundén, Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Militello Asp, Emilia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Binda, Federico
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Cecconello, Marco
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Conroy, Sean
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Dzysiuk, Natalia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Ericsson, Göran
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Eriksson, Jacob
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Hellesen, Carl
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Hjalmarsson, Anders
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Possnert, Göran
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Sjöstrand, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Skiba, Mateusz
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Weiszflog, Matthias
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Zychor, I.
    Inst Plasma Phys & Laser Microfus, PL-01497 Warsaw, Poland.
    The impact of poloidal asymmetries on tungsten transport in the core of JET H-mode plasmas2015Ingår i: Physics of Plasmas, ISSN 1070-664X, E-ISSN 1089-7674, Vol. 22, nr 5, artikel-id 055902Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Recent progress in the understanding and prediction of the tungsten behaviour in the core of JET H-mode plasmas with ITER-like wall is presented. Particular emphasis is given to the impact of poloidal asymmetries of the impurity density. In particular, it is shown that the predicted reduction of temperature screening induced by the presence of low field side localization of the tungsten density produced by the centrifugal force is consistent with the observed tungsten behaviour in a JET discharge in H-mode baseline scenario. This provides first evidence of the role of poloidal asymmetries in reducing the strength of temperature screening. The main differences between plasma parameters in JET baseline and hybrid scenario discharges which affect the impact of poloidally asymmetric density on the tungsten radial transport are identified. This allows the conditions by which tungsten accumulation can be avoided to be more precisely defined.

  • 41.
    Appel, L. C.
    et al.
    CCFE, Culham Science Centre, Abingdon, Oxfordshire, UK.
    Andersson Sundén, Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Binda, Federico
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Cecconello, Marco
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Conroy, Sean
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Dzysiuk, Nataliia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Ericsson, Göran
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Eriksson, Jacob
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Hellesen, Carl
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Hjalmarsson, Anders
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Possnert, Göran
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Sjöstrand, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Skiba, Mateusz
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Weiszflog, Matthias
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Zychor, I.
    Natl Ctr Nucl Res, Otwock, Poland.
    Equilibrium reconstruction in an iron core tokamak using a deterministic magnetisation model2018Ingår i: Computer Physics Communications, ISSN 0010-4655, E-ISSN 1879-2944, Vol. 223, s. 1-17Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In many tokamaks ferromagnetic material, usually referred to as an iron-core, is present in order to improve the magnetic coupling between the solenoid and the plasma. The presence of the iron core in proximity to the plasma changes the magnetic topology with consequent effects on the magnetic field structure and the plasma boundary. This paper considers the problem of obtaining the free-boundary plasma equilibrium solution in the presence of ferromagnetic material based on measured constraints. The current approach employs, a model described by O'Brien et al. (1992) in which the magnetisation currents at the iron-air boundary are represented by a set of free parameters and appropriate boundary conditions are enforced via a set of quasi-measurements on the material boundary. This can lead to the possibility of overfitting the data and hiding underlying issues with the measured signals. Although the model typically achieves good fits to measured magnetic signals there are significant discrepancies in the inferred magnetic topology compared with other plasma diagnostic measurements that are independent of the magnetic field. An alternative approach for equilibrium reconstruction in iron-core tokamaks, termed the deterministic magnetisation model is developed and implemented in EFIT++. The iron is represented by a boundary current with the gradients in the magnetisation dipole state generating macroscopic internal magnetisation currents. A model for the boundary magnetisation currents at the iron-air interface is developed using B-Splines enabling continuity to arbitrary order; internal magnetisation currents are allocated to triangulated regions within the iron, and a method to enable adaptive refinement is implemented. The deterministic model has been validated by comparing it with a synthetic 2-D electromagnetic model of JET. It is established that the maximum field discrepancy is less than 1.5 mT throughout the vacuum region enclosing the plasma. The discrepancies of simulated magnetic probe signals are accurate to within 1% for signals with absolute magnitude greater than 100 mT; in all other cases agreement is to within 1 mT. The effect of neglecting the internal magnetisation currents increases the maximum discrepancy in the vacuum region to >20 mT, resulting in errors of 5%-10% in the simulated probe signals. The fact that the previous model neglects the internal magnetisation currents (and also has additional free parameters when fitting the measured data) makes it unsuitable for analysing data in the absence of plasma current. The discrepancy of the poloidal magnetic flux within the vacuum vessel is to within 0.1 Wb. Finally the deterministic model is applied to an equilibrium force-balance solution of a JET discharge using experimental data. It is shown that the discrepancies of the outboard separatrix position, and the outer strike-point position inferred from Thomson Scattering and Infrared camera data are much improved beyond the routine equilibrium reconstruction, whereas the discrepancy of the inner strike-point position is similar. (C) 2017 Published by Elsevier B.V.

  • 42.
    Aran, A.
    et al.
    Univ Barcelona UB IEEC, Inst Ciencies Cosmos ICCUB, Dept Fis Quant & Astrofis, Barcelona, Spain..
    Pacheco, D.
    Univ Kiel, Inst Expt & Appl Phys, D-24118 Kiel, Germany..
    Laurenza, M.
    INAF Ist Astrofis & Planetol Spaziali, Via Fosso del Cavaliere 100, I-00133 Rome, Italy..
    Wijsen, N.
    Katholieke Univ Leuven, Ctr Math Plasma Astrophys, Dept Math, Celestijnenlaan 200B, B-3001 Leuven, Belgium..
    Lario, D.
    NASA Goddard Space Flight Ctr, Heliophys Sci Div, Greenbelt, MD 20771 USA..
    Benella, S.
    INAF Ist Astrofis & Planetol Spaziali, Via Fosso del Cavaliere 100, I-00133 Rome, Italy..
    Richardson, I. G.
    NASA Goddard Space Flight Ctr, Heliophys Sci Div, Greenbelt, MD 20771 USA.;Univ Maryland, Dept Astron, College Pk, MD 20742 USA..
    Samara, E.
    Katholieke Univ Leuven, Ctr Math Plasma Astrophys, Dept Math, Celestijnenlaan 200B, B-3001 Leuven, Belgium.;Royal Observ Belgium, Solar Terr Ctr Excellence SIDC, B-1180 Brussels, Belgium..
    von Forstner, J. L. Freiherr
    Univ Kiel, Inst Expt & Appl Phys, D-24118 Kiel, Germany.;Paradox Cat GmbH, D-80333 Munich, Germany..
    Sanahuja, B.
    Univ Barcelona UB IEEC, Inst Ciencies Cosmos ICCUB, Dept Fis Quant & Astrofis, Barcelona, Spain..
    Rodriguez, L.
    Royal Observ Belgium, Solar Terr Ctr Excellence SIDC, B-1180 Brussels, Belgium..
    Balmaceda, L.
    NASA Goddard Space Flight Ctr, Heliophys Sci Div, Greenbelt, MD 20771 USA.;George Mason Univ, Fairfax, VA 22030 USA..
    Lara, F. Espinosa
    Univ Alcala De Henares, Space Res Grp, Alcala De Henares 28805, Spain..
    Gomez-Herrero, R.
    Univ Alcala De Henares, Space Res Grp, Alcala De Henares 28805, Spain..
    Steinvall, Konrad
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Rymd- och plasmafysik.
    Vecchio, A.
    Univ Paris, LESIA, Observ Paris, Univ PSL,CNRS,Sorbonne Univ, 5 Pl Jules Janssen, F-92195 Meudon, France.;Radboud Univ Nijmegen, Dept Astrophys, Radboud Radio Lab, Nijmegen, Netherlands..
    Krupar, V
    NASA Goddard Space Flight Ctr, Heliophys Sci Div, Greenbelt, MD 20771 USA.;Univ Maryland Baltimore Cty, Goddard Planetary Heliophys Inst, Baltimore, MD 21228 USA..
    Poedts, S.
    Katholieke Univ Leuven, Ctr Math Plasma Astrophys, Dept Math, Celestijnenlaan 200B, B-3001 Leuven, Belgium.;Univ Maria Curie Sklodowska, Inst Phys, Ul Radziszewskiego 10, PL-20031 Lublin, Poland..
    Allen, R. C.
    Johns Hopkins Univ, Appl Phys Lab, Laurel, MD USA..
    Andrews, G. B.
    Johns Hopkins Univ, Appl Phys Lab, Laurel, MD USA..
    Angelini, V
    Imperial Coll London, Dept Phys, London SW7 2AZ, England..
    Berger, L.
    Univ Kiel, Inst Expt & Appl Phys, D-24118 Kiel, Germany..
    Berghmans, D.
    Royal Observ Belgium, Solar Terr Ctr Excellence SIDC, B-1180 Brussels, Belgium..
    Boden, S.
    Univ Kiel, Inst Expt & Appl Phys, D-24118 Kiel, Germany.;DSI Datensicherheit GmbH, Rodendamm 34, D-28816 Stuhr, Germany..
    Bottcher, S. , I
    Carcaboso, F.
    Univ Alcala De Henares, Space Res Grp, Alcala De Henares 28805, Spain..
    Cernuda, I
    Univ Alcala De Henares, Space Res Grp, Alcala De Henares 28805, Spain..
    De Marco, R.
    INAF Ist Astrofis & Planetol Spaziali, Via Fosso del Cavaliere 100, I-00133 Rome, Italy..
    Eldrum, S.
    Univ Kiel, Inst Expt & Appl Phys, D-24118 Kiel, Germany..
    Evans, V
    Imperial Coll London, Dept Phys, London SW7 2AZ, England..
    Fedorov, A.
    Inst Rech Astrophys & Planetol, 9 Ave Colonel Roche,BP 4346, F-31028 Toulouse 4, France..
    Hayes, J.
    Johns Hopkins Univ, Appl Phys Lab, Laurel, MD USA..
    Ho, G. C.
    Johns Hopkins Univ, Appl Phys Lab, Laurel, MD USA..
    Horbury, T. S.
    Imperial Coll London, Dept Phys, London SW7 2AZ, England..
    Janitzek, N. P.
    European Space Astron Ctr ESAC, European Space Agcy ESA, Madrid, Spain..
    Khotyaintsev, Yuri V.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Kollhoff, A.
    Univ Kiel, Inst Expt & Appl Phys, D-24118 Kiel, Germany..
    Kuehl, P.
    Univ Kiel, Inst Expt & Appl Phys, D-24118 Kiel, Germany..
    Kulkarni, S. R.
    Univ Kiel, Inst Expt & Appl Phys, D-24118 Kiel, Germany.;Deutsch Elektronen Synchrotron DESY, Platanenallee 6, D-15738 Zeuthen, Germany..
    Lees, W. J.
    Johns Hopkins Univ, Appl Phys Lab, Laurel, MD USA..
    Louarn, P.
    Inst Rech Astrophys & Planetol, 9 Ave Colonel Roche,BP 4346, F-31028 Toulouse 4, France..
    Magdalenic, J.
    Katholieke Univ Leuven, Ctr Math Plasma Astrophys, Dept Math, Celestijnenlaan 200B, B-3001 Leuven, Belgium.;Royal Observ Belgium, Solar Terr Ctr Excellence SIDC, B-1180 Brussels, Belgium..
    Maksimovic, M.
    Univ Paris, LESIA, Observ Paris, Univ PSL,CNRS,Sorbonne Univ, 5 Pl Jules Janssen, F-92195 Meudon, France..
    Malandraki, O.
    Natl Observ Athens, Inst Astron Astrophys Space Applicat & Remote Sen, Athens, Greece..
    Martinez, A.
    Univ Alcala De Henares, Space Res Grp, Alcala De Henares 28805, Spain..
    Mason, G. M.
    Johns Hopkins Univ, Appl Phys Lab, Laurel, MD USA..
    Martin, C.
    Univ Kiel, Inst Expt & Appl Phys, D-24118 Kiel, Germany.;German Aerosp Ctr DLR, Dept Extrasolar Planets & Atmospheres, Berlin, Germany..
    O'Brien, H.
    Imperial Coll London, Dept Phys, London SW7 2AZ, England..
    Owen, C.
    Univ Coll London, Dept Space & Climate Phys, Dorking RH5 6NT, Surrey, England..
    Parra, P.
    Univ Alcala De Henares, Space Res Grp, Alcala De Henares 28805, Spain..
    Prieto Mateo, M.
    Univ Alcala De Henares, Space Res Grp, Alcala De Henares 28805, Spain..
    Ravanbakhsh, A.
    Univ Kiel, Inst Expt & Appl Phys, D-24118 Kiel, Germany.;Max Planck Inst Solar Syst Res, Justus von Liebig Weg 3, D-37077 Gottingen, Germany..
    Rodriguez-Pacheco, J.
    Univ Alcala De Henares, Space Res Grp, Alcala De Henares 28805, Spain..
    Rodriguez Polo, O.
    Univ Alcala De Henares, Space Res Grp, Alcala De Henares 28805, Spain..
    Sanchez Prieto, S.
    Univ Alcala De Henares, Space Res Grp, Alcala De Henares 28805, Spain..
    Schlemm, C. E.
    Johns Hopkins Univ, Appl Phys Lab, Laurel, MD USA..
    Seifert, H.
    Johns Hopkins Univ, Appl Phys Lab, Laurel, MD USA..
    Terasa, J. C.
    Univ Kiel, Inst Expt & Appl Phys, D-24118 Kiel, Germany..
    Tyagi, K.
    Johns Hopkins Univ, Appl Phys Lab, Laurel, MD USA.;Univ Colorado, LASP, Boulder, CO 80309 USA..
    Verbeeck, C.
    Royal Observ Belgium, Solar Terr Ctr Excellence SIDC, B-1180 Brussels, Belgium..
    Wimmer-Schweingruber, R. F.
    Univ Kiel, Inst Expt & Appl Phys, D-24118 Kiel, Germany..
    Xu, Z. G.
    Univ Kiel, Inst Expt & Appl Phys, D-24118 Kiel, Germany..
    Yedla, M. K.
    Univ Kiel, Inst Expt & Appl Phys, D-24118 Kiel, Germany.;Max Planck Inst Solar Syst Res, Justus von Liebig Weg 3, D-37077 Gottingen, Germany..
    Zhukov, A. N.
    Royal Observ Belgium, Solar Terr Ctr Excellence SIDC, B-1180 Brussels, Belgium.;Moscow MV Lomonosov State Univ, Skobeltsyn Inst Nucl Phys, Moscow, Russia..
    Evidence for local particle acceleration in the first recurrent galactic cosmic ray depression observed by Solar Orbiter: The ion event on 19 June 20202021Ingår i: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 656, artikel-id L10Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Context. In mid-June 2020, the Solar Orbiter (SolO) mission reached its first perihelion at 0.51 au and started its cruise phase, with most of the in situ instruments operating continuously.

    Aims. We present the in situ particle measurements of the first proton event observed after the first perihelion obtained by the Energetic Particle Detector (EPD) suite on board SolO. The potential solar and interplanetary (IP) sources of these particles are investigated.

    Methods. Ion observations from similar to 20 keV to similar to 1 MeV are combined with available solar wind data from the Radio and Plasma Waves (RPW) instrument and magnetic field data from the magnetometer on board SolO to evaluate the energetic particle transport conditions and infer the possible acceleration mechanisms through which particles gain energy. We compare > 17-20 MeV ion count rate measurements for two solar rotations, along with the solar wind plasma data available from the Solar Wind Analyser (SWA) and RPW instruments, in order to infer the origin of the observed galactic cosmic ray (GCR) depressions.

    Results. The lack of an observed electron event and of velocity dispersion at various low-energy ion channels and the observed IP structure indicate a local IP source for the low-energy particles. From the analysis of the anisotropy of particle intensities, we conclude that the low-energy ions were most likely accelerated via a local second-order Fermi process. The observed GCR decrease on 19 June, together with the 51.8-1034.0 keV nuc(-1) ion enhancement, was due to a solar wind stream interaction region (SIR). The observation of a similar GCR decrease in the next solar rotation favours this interpretation and constitutes the first observation of a recurrent GCR decrease by SolO. The analysis of the recurrence times of this SIR suggests that it is the same SIR responsible for the He-4 events previously measured in April and May. Finally, we point out that an IP structure more complex than a common SIR cannot be discarded, mainly due to the lack of solar wind temperature measurements and the lack of a higher cadence of solar wind velocity observations.

  • 43.
    Argall, M. R.
    et al.
    Univ New Hampshire, Ctr Space Sci, Durham, NH USA.
    Paulson, K.
    Univ New Hampshire, Ctr Space Sci, Durham, NH USA.
    Alm, L.
    Univ New Hampshire, Ctr Space Sci, Durham, NH USA.
    Rager, A.
    NASA, Goddard Space Flight Ctr, Greenbelt, MD USA.
    Dorelli, J.
    NASA, Goddard Space Flight Ctr, Greenbelt, MD USA.
    Shuster, J.
    NASA, Goddard Space Flight Ctr, Greenbelt, MD USA.
    Wang, S.
    NASA, Goddard Space Flight Ctr, Greenbelt, MD USA.
    Torbert, R. B.
    Univ New Hampshire, Ctr Space Sci, Durham, NH USA; Southwest Res Inst, San Antonio, TX USA.
    Vaith, H.
    Univ New Hampshire, Ctr Space Sci, Durham, NH USA.
    Dors, I.
    Univ New Hampshire, Ctr Space Sci, Durham, NH USA.
    Chutter, M.
    Univ New Hampshire, Ctr Space Sci, Durham, NH USA.
    Farrugia, C.
    Univ New Hampshire, Ctr Space Sci, Durham, NH USA.
    Burch, J.
    Southwest Res Inst, San Antonio, TX USA.
    Pollock, C.
    NASA, Goddard Space Flight Ctr, Greenbelt, MD USA.
    Giles, B.
    NASA, Goddard Space Flight Ctr, Greenbelt, MD USA.
    Gershman, D.
    NASA, Goddard Space Flight Ctr, Greenbelt, MD USA.
    Lavraud, B.
    Univ Toulouse, CNRS, Inst Rech Astrophys & Planetol, UPS, Toulouse, France..
    Russell, C. T.
    Univ Calif Los Angeles, Earth Planetary & Space Sci, Los Angeles, CA USA..
    Strangeway, R.
    Univ Calif Los Angeles, Earth Planetary & Space Sci, Los Angeles, CA USA..
    Magnes, W.
    Austrian Acad Sci, Space Res Inst, Graz, Austria.
    Lindqvist, P. -A
    KTH Royal Inst Technol, Stockholm, Sweden.
    Khotyaintsev, Yuri V.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen.
    Ergun, R. E.
    Univ Colorado Boulder, Boulder, CO USA.
    Ahmadi, N.
    Univ Colorado Boulder, Boulder, CO USA.
    Electron Dynamics Within the Electron Diffusion Region of Asymmetric Reconnection2018Ingår i: Journal of Geophysical Research - Space Physics, ISSN 2169-9380, E-ISSN 2169-9402, Vol. 123, nr 1, s. 146-162Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Abstract: We investigate the agyrotropic nature of electron distribution functions and their substructure to illuminate electron dynamics in a previously reported electron diffusion region (EDR) event. In particular, agyrotropy is examined as a function of energy to reveal detailed finite Larmor radius effects for the first time. It is shown that the previously reported approximate to 66eV agyrotropic "crescent" population that has been accelerated as a result of reconnection is evanescent in nature because it mixes with a denser, gyrotopic background. Meanwhile, accelerated agyrotropic populations at 250 and 500eV are more prominent because the background plasma at those energies is more tenuous. Agyrotropy at 250 and 500eV is also more persistent than at 66eV because of finite Larmor radius effects; agyrotropy is observed 2.5 ion inertial lengths from the EDR at 500eV, but only in close proximity to the EDR at 66eV. We also observe linearly polarized electrostatic waves leading up to and within the EDR. They have wave normal angles near 90 degrees, and their occurrence and intensity correlate with agyrotropy. Within the EDR, they modulate the flux of 500eV electrons travelling along the current layer. The net electric field intensifies the reconnection current, resulting in a flow of energy from the fields into the plasma.

    Plain Language Summary: The process of reconnection involves an explosive transfer of magnetic energy into particle energy. When energetic particles contact modern technology such as satellites, cell phones, or other electronic devices, they can cause random errors and failures. Exactly how particles are energized via reconnection, however, is still unknown. Fortunately, the Magnetospheric Multiscale mission is finally able to detect and analyze reconnection processes. One recent finding is that energized particles take on a crescent-shaped configuration in the vicinity of reconnection and that this crescent shape is related to the energy conversion process. In our paper, we explain why the crescent shape has not been observed until now and inspect particle motions to determine what impact it has on energy conversion. When reconnection heats the plasma, the crescent shape forms from the cool, tenuous particles. As plasmas from different regions mix, dense, nonheated plasma obscures the crescent shape in our observations. The highest-energy particle population created by reconnection, though, also contains features of the crescent shape that are more persistent but appear less dramatically in the data.

    Ladda ner fulltext (pdf)
    fulltext
  • 44.
    Arnichand, H.
    et al.
    CEA, IRFM, F-13108 St Paul Les Durance, France;IRFM, CEA, F-13108 St Paul Les Durance, France.
    Andersson Sundén, Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Militello Asp, Emilia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Binda, Federico
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Cecconello, Marco
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Conroy, Sean
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Dzysiuk, Natalia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Ericsson, Göran
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Eriksson, Jacob
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Hellesen, Carl
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Hjalmarsson, Anders
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Possnert, Göran
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Sjöstrand, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Skiba, Mateusz
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Weiszflog, Matthias
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Zychor, I.
    Inst Plasma Phys & Laser Microfus, PL-01497 Warsaw, Poland.
    Discriminating the trapped electron modes contribution in density fluctuation spectra2015Ingår i: Nuclear Fusion, ISSN 0029-5515, E-ISSN 1741-4326, Vol. 55, nr 9, artikel-id 093021Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Quasi-coherent (QC) modes have been reported for more than 10 years in reflectometry fluctuations spectra in the core region of fusion plasmas. They have characteristics in-between coherent and broadband fluctuations as they oscillate at a marked frequency but have a wide spectrum. This work presents further evidences of the link recently established between QC modes and the trapped electron modes (TEM) instabilities (Arnichand et al 2014 Nucl. Fusion 54 123017). In electron cyclotron resonance heated discharges of Tore Supra, an enhancement of QC modes amplitude is observed in a region where TEM cause impurity transport and turbulence. In JET Ohmic plasmas, QC modes disappear during density ramp-up and current ramp-down. This is reminiscent of Tore Supra and TEXTOR observations during transitions from the linear Ohmic confinement (LOC) to the saturated Ohmic confinement (SOC) regimes. Evidencing TEM activity then becomes experimentally possible via analysis of fluctuation spectra.

  • 45.
    Ashraf, Shakeel
    et al.
    Mid Sweden Univ, Dept Elect Design, Sundsvall, Sweden..
    Mattsson, Claes G.
    Mid Sweden Univ, Dept Elect Design, Sundsvall, Sweden..
    Fondell, Mattis
    Helmholtz Zentrum, Inst Methods & Instrumentat Synchrotron Radiat Re, Berlin, Germany..
    Lindblad, Andreas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Molekyl- och kondenserade materiens fysik.
    Thungström, Göran
    Mid Sweden Univ, Dept Elect Design, Sundsvall, Sweden..
    Surface modification of SU-8 for metal/SU-8 adhesion using RF plasma treatment for application in thermopile detectors2015Ingår i: Materials Research Express, E-ISSN 2053-1591, Vol. 2, nr 8, artikel-id 086501Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This article reports on plasma treatment of SU-8 epoxy in order to enhance adhesive strength for metals. Its samples were fabricated on standard silicon wafers and treated with (O-2 and Ar) RF plasma at a power of 25 W at a low pressure of (3 x 10(-3) Torr) for different time spans (10-70 s). The sample surfaces were characterized in terms of contact angle, surface (roughness and chemistry) and using a tape test. During the contact angle measurement, it was observed that the contact angle was reduced from 73 degrees to 5 degrees (almost wet) and 23 degrees for (O-2 and Ar) treated samples, respectively. The root mean square surface roughness was significantly increased by 21.5% and 37.2% for (O-2 and Ar) treatment, respectively. A pattern of metal squares was formed on the samples using photolithography for a tape test. An adhesive tape was applied to the samples and peeled off at 180 degrees The maximum adhesion results, more than 90%, were achieved for the O-2-treated samples, whereas the Ar-treated samples showed no change. The XPS study shows the formation of new species in the O-2-treated sample compared to the Ar-treated samples. The high adhesive results were due to the formation of hydrophilic groups and new O-2 species in the O-2-treated samples, which were absent in Ar-treated samples.

  • 46. Aslanyan, V
    et al.
    Andersson Sundén, Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Binda, F.
    Cecconello, M.
    Conroy, Sean
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Dzysiuk, N.
    Ericsson, Göran
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Eriksson, Jacob
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Hellesen, C.
    Hjalmarsson, Anders
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Possnert, Göran
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Sjöstrand, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Skiba, M.
    Weiszflog, Matthias
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Zychor, I.
    Gyrokinetic simulations of toroidal Alfven eigenmodes excited by energetic ions and external antennas on the Joint European Torus2019Ingår i: Nuclear Fusion, ISSN 0029-5515, E-ISSN 1741-4326, Vol. 59, nr 2, artikel-id 026008Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The gyrokinetic toroidal code (GTC) has been used to study toroidal Alfven eigenmodes (TAEs) in high-performance plasmas. Experiments performed at the Joint European Torus (JET), where TAEs were driven by energetic particles arising from neutral beams, ion cyclotron resonant heating, and resonantly excited by dedicated external antennas, have been simulated. Modes driven by populations of energetic particles are observed, matching the TAE frequency seen with magnetic probes in JET experiments. A synthetic antenna, composed of one toroidal and two neighboring poloidal harmonics has been used to probe the modes' damping rates and quantify mechanisms for this damping in GTC simulations. This method was also applied to frequency and damping rate measurements of stable TAEs made by the Alfven eigenmode active diagnostic in these discharges.

  • 47.
    Asp, Elina
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för astronomi och rymdfysik.
    Drift-Type Waves in Rotating Tokamak Plasma2003Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The concept of energy production through the fusion of two light nuclei has been studied since the 1950’s. One of the major problems that fusion scientists have encountered is the confinement of the hot ionised gas, i.e. the plasma, in which the fusion process takes place. The most common way to contain the plasma is by using at magnetic field configuration, in which the plasma takes a doughnut-like shape. Experimental devices of this kind are referred to as tokamaks. For the fusion process to proceed at an adequate rate, the temperature of the plasma must exceed 100,000,000C. Such a high temperature forces the plasma out of thermodynamical equilibrium which plasma tries to regain by exciting a number of turbulent processes. After successfully quenching the lager scale magnetohydrodynamic turbulence that may instantly disrupt the plasma, a smaller scale turbulence revealed itself. As this smaller scale turbulence behaved contrary to the common theory at the time, it was referred to as anomalous. This kind of turbulence does not directly threaten existents of the plasma, but it allows for a leakage of heat and particles which inhibits the fusion reactions. It is thus essential to understand the origin of anomalous turbulence, the transport it generates and most importantly, how to reduce it. Today it is believed that anomalous transport is due to drift-type waves driven by temperature and density inhomogeneities and the theoretical treatment of these waves is the topic of this thesis.

    The first part of the thesis contains a rigorous analytical two-fluid treatment of drift waves driven solely by density inhomogeneities. Effects of the toroidal magnetic field configuration, the Landau resonance, a peaked diamagnetic frequency and a sheared rotation of the plasma have been taken into account. These effects either stabilise or destabilise the drift waves and to determine the net result on the drift waves requires careful analysis. To this end, dispersion relations have been obtained in various limits to determine when to expect the different effects to be dominant. The main result of this part is that with a large enough rotational shear, the drift waves will be quenched.

    In the second part we focus on temperature effects and thus treat reactive drift waves, specifically ion temperature gradient and trapped electron modes. In fusion plasmas the α-particles, created as a by-product of the fusion process, transfer the better part of their energy to the electrons and hence the electron temperature is expected to exceed the ion temperature. In most experiments until today, the ion temperature is greater than the electron temperature and this have been proven to improve the plasma confinement. To predict the performance of future fusion plasmas, where the fusion process is ongoing, a comprehensive study of hot-electron plasmas and external heating effects have been carried out. Especially the stiffness (heat flux vs. inverse temperature length scale) of the plasma has been examined. This work was performed by simulations done with the JETTO code utilising the Weiland model. The outcome of these simulations shows that the plasma response to strong heating is very stiff and that the plasma energy confinement time seems to vary little in the hot-electron mode.

    Delarbeten
    1. Ship-Wave Eigenmodes of Drift Type in Rotating Tokamak Plasmas
    Öppna denna publikation i ny flik eller fönster >>Ship-Wave Eigenmodes of Drift Type in Rotating Tokamak Plasmas
    2000 (Engelska)Ingår i: Physica scripta. T, ISSN 0281-1847, Vol. 62, nr 2-3, s. 169-176Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Ship waves of drift type in rotating plasma of axisymmetric, large aspect-ratio tokamaks with concentric, circular magnetic surfaces are investigated. Plasma rotation is driven by an electrostatic radial electric field and the waves under consideration may be excited by plasma flow past some static obstacle. The analysis performed is based on rigorously derived eigenmode equations coupled in poloidal mode numbers through toroidal effects. The existence of two qualitatively different types of ship wave eigenmodes is demonstrated. Namely (i) global modes that have a structure of quasimodes localised in both radial and poloidal directions and correspond to the bounded states in a potential well which are marginally stable and (ii) propagating modes that experience shear convective damping. The dispersion relations for both types of eigenmodes are obtained both in the weak and the strong coupling approximation.

    We find the analytical solutions of the dispersion relations and the regions of their existence which are defined, mainly, by the value and direction of the poloidal rotation velocity. An accumulation point for global ship eigenmodes is determined. For propagating ship waves the real and the imaginary parts of the poloidal wavenumber are found. It is shown that the imaginary part always corresponds to convective damping of these waves

    Nyckelord
    Ship waves of drift type in rotating plasma of axisymmetric, large aspect-ratio tokamaks with concentric, circular magnetic surfaces are investigated. Plasma rotation is driven by an electrostatic radial electric field and the waves under consideration ma
    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:uu:diva-90344 (URN)10.1238/Physica.Regular.062a00169 (DOI)
    Tillgänglig från: 2003-05-15 Skapad: 2003-05-15 Senast uppdaterad: 2017-12-14Bibliografiskt granskad
    2. Localising Effects of a Peaked Diamagnetic Frequency on Drift Modes in Rotating Tokamak Plasmas
    Öppna denna publikation i ny flik eller fönster >>Localising Effects of a Peaked Diamagnetic Frequency on Drift Modes in Rotating Tokamak Plasmas
    2002 (Engelska)Ingår i: Physica scripta. T, ISSN 0281-1847, Vol. T98, nr -, s. 151-154Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    In this paper we investigate the effects of a diamagnetic frequency peaking and velocity shear on a two-dimensional drift mode structure. Previous study made by Horton et al. showed that a strong diamagnetic frequency peaking can trap the wave energy both radially and along the magnetic field lines. We show that the localising effect of the diamagnetic frequency peaking can be suppressed by a strong velocity shear in the edge plasma. The same phenomenon is present in the bulk plasma, but due to the velocity shear not being as pronounced there, the effect is nominal.

    Nationell ämneskategori
    Fusion, plasma och rymdfysik
    Identifikatorer
    urn:nbn:se:uu:diva-90345 (URN)10.1238/Physica.Topical.098a00151 (DOI)
    Tillgänglig från: 2003-05-15 Skapad: 2003-05-15 Senast uppdaterad: 2017-12-14Bibliografiskt granskad
    3. Stability of the Landau Resonance for Drift Modes in Rotating Tokamak Plasma
    Öppna denna publikation i ny flik eller fönster >>Stability of the Landau Resonance for Drift Modes in Rotating Tokamak Plasma
    2003 (Engelska)Ingår i: Journal of Plasma Physics, ISSN 0022-3778, E-ISSN 1469-7807, Vol. 60, nr 5, s. 371-Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    The linear stability of drift waves in a poloidally rotating tokamak plasma is considered. The derived dispersion relation features a peaking of the diamagnetic frequency which gives the drift modes an irreducible two-dimensional character. We then show that inverse Landau damping can be suppressed and even stabilized, if the flow's shear is strong. Even though the instability, excited by the Landau resonance, is stronger at a high velocity shear for positive rotation velocities, effects due to the rotation of the plasma can reverse the sign and induce damping of the two-dimensional drift modes. This stabilizing mechanism works only for positive rotation velocities. For negative rotation velocities, we show that only modes with high poloidal mode numbers are unstable.

    Nationell ämneskategori
    Fusion, plasma och rymdfysik
    Identifikatorer
    urn:nbn:se:uu:diva-90346 (URN)10.1017/S0022377803002253 (DOI)
    Tillgänglig från: 2003-05-15 Skapad: 2003-05-15 Senast uppdaterad: 2017-12-14Bibliografiskt granskad
    4. JETTO Simulations of Te/Ti Effects on Plasma Confinement
    Öppna denna publikation i ny flik eller fönster >>JETTO Simulations of Te/Ti Effects on Plasma Confinement
    Visa övriga...
    Manuskript (Övrigt vetenskapligt)
    Identifikatorer
    urn:nbn:se:uu:diva-90347 (URN)
    Tillgänglig från: 2003-05-15 Skapad: 2003-05-15 Senast uppdaterad: 2010-01-13Bibliografiskt granskad
    Ladda ner fulltext (pdf)
    FULLTEXT01
  • 48.
    Asp, Elina
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för astronomi och rymdfysik.
    Pavlenko, Vladimir P.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för astronomi och rymdfysik.
    Revenchuk, Sergey M.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för astronomi och rymdfysik.
    Localising Effects of a Peaked Diamagnetic Frequency on Drift Modes in Rotating Tokamak Plasmas2002Ingår i: Physica scripta. T, ISSN 0281-1847, Vol. T98, nr -, s. 151-154Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper we investigate the effects of a diamagnetic frequency peaking and velocity shear on a two-dimensional drift mode structure. Previous study made by Horton et al. showed that a strong diamagnetic frequency peaking can trap the wave energy both radially and along the magnetic field lines. We show that the localising effect of the diamagnetic frequency peaking can be suppressed by a strong velocity shear in the edge plasma. The same phenomenon is present in the bulk plasma, but due to the velocity shear not being as pronounced there, the effect is nominal.

  • 49.
    Asp, Elina
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för astronomi och rymdfysik.
    Pavlenko, Vladimir P.
    Revenchuk, Sergey M.
    Stability of the Landau Resonance for Drift Modes in Rotating Tokamak Plasma2003Ingår i: Journal of Plasma Physics, ISSN 0022-3778, E-ISSN 1469-7807, Vol. 60, nr 5, s. 371-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The linear stability of drift waves in a poloidally rotating tokamak plasma is considered. The derived dispersion relation features a peaking of the diamagnetic frequency which gives the drift modes an irreducible two-dimensional character. We then show that inverse Landau damping can be suppressed and even stabilized, if the flow's shear is strong. Even though the instability, excited by the Landau resonance, is stronger at a high velocity shear for positive rotation velocities, effects due to the rotation of the plasma can reverse the sign and induce damping of the two-dimensional drift modes. This stabilizing mechanism works only for positive rotation velocities. For negative rotation velocities, we show that only modes with high poloidal mode numbers are unstable.

  • 50.
    Backrud, Marie
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för astronomi och rymdfysik.
    Cluster Observations and Theoretical Explanations of Broadband Waves in the Auroral Region2005Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Broadband extremely low-frequency wave emissions below the ion plasma frequency have been observed by a number of spacecraft and rockets on auroral field lines. The importance of these broadband emissions for transverse ion heating and electron acceleration in the auroral regions is now reasonably well established. However, the exact mechanism(s) for mediating this energy transfer and the wave mode(s) involved are not well known. In this thesis we focus on the identification of broadband waves by different methods.

    Two wave analysis methods, involving different approximations and assumptions, give consistent results concerning the wave mode identification. We find that much of the broadband emissions can be identified as a mixture of ion acoustic, electrostatic ion cyclotron and, ion Bernstein waves, which all can be described as different parts of the same dispersion surface in the linear theory of waves in homogeneous plasma.

    A new result is that ion acoustic waves occur on auroral magnetic field lines. These are found in relatively small regions interpreted as acceleration regions without cold (tens of eV) electrons.

    From interferometry we also determine the phase velocity and k vector for parallel and oblique ion acoustic waves. The retrieved characteristic phase velocity is of the order of the ion acoustic speed and larger than the thermal velocity of the protons. The typical wavelength is around the proton gyro radius and always larger than the Debye length which is consistent with ion acoustic waves.

    We have observed quasi-static parallel electric fields associated with the ion acoustic waves in regions with large-scale currents. Waves, in particular ion acoustic waves, can create an anomalous resistivity due to wave-particle interaction when electrons are retarded or trapped by the electric wave-field. To maintain the large-scale current, a parallel electric field is set up, which then can accelerate a second electron population to high velocities.

    Delarbeten
    1. Identification of Broadband Waves Above the Auroral Acceleration Region: CLUSTER Observations
    Öppna denna publikation i ny flik eller fönster >>Identification of Broadband Waves Above the Auroral Acceleration Region: CLUSTER Observations
    Visa övriga...
    2004 Ingår i: Annales Geophysicae, ISSN 0992-7689, Vol. 22, nr 12, s. 14-Artikel i tidskrift (Refereegranskat) Published
    Identifikatorer
    urn:nbn:se:uu:diva-93091 (URN)
    Tillgänglig från: 2005-05-11 Skapad: 2005-05-11 Senast uppdaterad: 2014-11-12Bibliografiskt granskad
    2. Cluster observations and theoretical identification of broadband waves in the auroral region
    Öppna denna publikation i ny flik eller fönster >>Cluster observations and theoretical identification of broadband waves in the auroral region
    Visa övriga...
    2005 (Engelska)Ingår i: Annales Geophysicae, ISSN 0992-7689, E-ISSN 1432-0576, Vol. 23, nr 12, s. 3739-3752Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Broadband waves are common on auroral field lines. We use two different methods to study the polarization of the waves at 10 to 180 Hz observed by the Cluster spacecraft at altitudes of about 4 Earth radii in the nightside auroral region. Observations of electric and magnetic wave fields, together with electron and ion data, are used as input to the methods. We find that much of the wave emissions are consistent with linear waves in homogeneous plasma. Observed waves with a large electric field perpendicular to the geomagnetic field are more common (electrostatic ion cyclotron waves), while ion acoustic waves with a large parallel electric field appear in smaller regions without suprathermal (tens of eV) plasma. The regions void of suprathermal plasma are interpreted as parallel potential drops of a few hundred volts.

    Nationell ämneskategori
    Fysik
    Identifikatorer
    urn:nbn:se:uu:diva-93092 (URN)10.5194/angeo-23-3739-2005 (DOI)000235008400015 ()
    Tillgänglig från: 2005-05-11 Skapad: 2005-05-11 Senast uppdaterad: 2017-12-14Bibliografiskt granskad
    3. Interferometric Identification of Ion Acoustic Broadband Waves in the Auroral Region: CLUSTER Observations
    Öppna denna publikation i ny flik eller fönster >>Interferometric Identification of Ion Acoustic Broadband Waves in the Auroral Region: CLUSTER Observations
    Visa övriga...
    2005 (Engelska)Ingår i: Geophysical Research Letters, ISSN 0094-8276, E-ISSN 1944-8007, Vol. 32, nr 21Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    [1] We determine the phase velocity and k vector for parallel and oblique broadband extremely low frequency, ELF, waves on nightside auroral magnetic field lines at altitudes around 4.6 RE. We use internal burst mode data from the EFW electric field and wave instrument onboard the Cluster spacecraft to retrieve phase differences between the four probes of the instrument. The retrieved characteristic phase velocity is of the order of the ion acoustic speed and larger than the thermal velocity of the protons. The typical wavelength obtained from interferometry is around the proton gyro radius and always larger than the Debye length. We find that in regions with essentially no suprathermal electrons above a few tens of eV the observed broadband waves above the proton gyro frequency are consistent with upgoing ion acoustic and oblique ion acoustic waves.

    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:uu:diva-93093 (URN)10.1029/2005GL022640 (DOI)
    Tillgänglig från: 2005-05-11 Skapad: 2005-05-11 Senast uppdaterad: 2017-12-14Bibliografiskt granskad
    4. Direct Observations of Electric Fields and Particle Acceleration Caused by Anomalous Wave-Particle Resistivity in Space Plasmas
    Öppna denna publikation i ny flik eller fönster >>Direct Observations of Electric Fields and Particle Acceleration Caused by Anomalous Wave-Particle Resistivity in Space Plasmas
    Visa övriga...
    Manuskript (Övrigt vetenskapligt)
    Identifikatorer
    urn:nbn:se:uu:diva-93094 (URN)
    Tillgänglig från: 2005-05-11 Skapad: 2005-05-11 Senast uppdaterad: 2010-01-13Bibliografiskt granskad
    Ladda ner fulltext (pdf)
    FULLTEXT01
    Ladda ner (pdf)
    COVER01
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  • ieee
  • modern-language-association
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf