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BETA
Zlomanczuk, Jozef
Alternative names
Publications (10 of 52) Show all publications
Adlarson, P., Augustyniak, W., Bardan, W., Bashkanov, M., Bergmann, F. S., Berlowski, M., . . . Zurek, M. (2019). Examination of the production of an isotensor dibaryon in the pp -> pp pi(+)pi(-) reaction. Physical Review C: Covering Nuclear Physics, 99(2), Article ID 025201.
Open this publication in new window or tab >>Examination of the production of an isotensor dibaryon in the pp -> pp pi(+)pi(-) reaction
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2019 (English)In: Physical Review C: Covering Nuclear Physics, ISSN 2469-9985, E-ISSN 2469-9993, Vol. 99, no 2, article id 025201Article in journal (Refereed) Published
Abstract [en]

The quasifree pp -> pp pi(+)pi(-) reaction has been measured by means of pd collisions at T-p = 1.2 GeV using the WASA detector setup at COSY enabling exclusive and kinematically complete measurements. Total and differential cross sections have been extracted for the energy region T-p = 1.08-1.36 GeV (root s = 2.35-2.46 GeV) covering thus the regions of N* (1440 ) and Delta(1232)Delta(1232) resonance excitations. Calculations describing these excitations by t-channel meson exchange as well as isospin relations based on the pp -> pp pi(0)pi(0) data underpredict substantially the measured total cross section. The calculations are also at variance with specific experimental differential cross sections. An isotensor Delta N dibaryon resonance with I(J(P)) = 2(1(+) ) produced associatedly with a pion is able to overcome these deficiencies. Such a dibaryon was predicted by Dyson and Xuong [Phys. Rev. Lett. 13, 815 (1964)] and more recently calculated by A. Gal and H. Garcilazo [Nucl. Phys. A 928, 73 (2014)].

Place, publisher, year, edition, pages
AMER PHYSICAL SOC, 2019
National Category
Subatomic Physics
Identifiers
urn:nbn:se:uu:diva-377601 (URN)10.1103/PhysRevC.99.025201 (DOI)000457696100003 ()
Available from: 2019-02-26 Created: 2019-02-26 Last updated: 2019-03-07Bibliographically approved
Adlarson, P., Augustyniak, W., Bardan, W., Bashkanov, M., Bergmann, F. S., Berlowski, M., . . . Wilkin, C. (2018). Backward single-pion production in the pd -> He-3 pi(0)reaction with WASA-at-COSY. European Physical Journal A, 54(9), Article ID 149.
Open this publication in new window or tab >>Backward single-pion production in the pd -> He-3 pi(0)reaction with WASA-at-COSY
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2018 (English)In: European Physical Journal A, ISSN 1434-6001, E-ISSN 1434-601X, Vol. 54, no 9, article id 149Article in journal (Refereed) Published
Abstract [en]

New data on the production of single neutral pions in the pd -> He-3 pi(0) reaction are presented. For fifteen proton beam momenta between p(p) = 1.60GeV/c and p(p) = 1.74 GeV/c, differential cross sections are determined over a large fraction of the backward hemisphere. Since the only previous systematic measurements of single-pion production at these energies were made in collinear kinematics, the present work constitutes a significant extension of the current knowledge on this reaction. Even this far above the production threshold, significant changes are found in the behaviour of the angular distributions over small intervals in beam momentum.

Place, publisher, year, edition, pages
SPRINGER, 2018
National Category
Astronomy, Astrophysics and Cosmology Subatomic Physics
Identifiers
urn:nbn:se:uu:diva-366738 (URN)10.1140/epja/i2018-12585-3 (DOI)000444638600001 ()
Funder
EU, FP7, Seventh Framework Programme, 283286
Available from: 2018-12-10 Created: 2018-12-10 Last updated: 2018-12-10Bibliographically approved
Adlarson, P., Augustyniak, W., Bardan, W., Bashkanov, M., Bergmann, F. S., Berlowski, M., . . . Zurek, M. (2018). Importance of d-wave contributions in the charge symmetry breaking reaction dd -> He-4 pi(0). Physics Letters B, 781, 645-650
Open this publication in new window or tab >>Importance of d-wave contributions in the charge symmetry breaking reaction dd -> He-4 pi(0)
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2018 (English)In: Physics Letters B, ISSN 0370-2693, E-ISSN 1873-2445, Vol. 781, p. 645-650Article in journal (Refereed) Published
Abstract [en]

This letter reports a first quantitative analysis of the contribution of higher partial waves in the charge symmetry breaking reaction dd -> He-4 pi(0) using the WASA-at-COSY detector setup at an excess energy of Q = 60 MeV. The determined differential cross section can be parametrized as d sigma/d Omega = a + b cos(2) theta*, where theta* is the production angle of the pion in the center-of-mass coordinate system, and the results for the parameters are a = (1.55 +/- 0.46(stat)(-0.8)(+0.32)(syst)) pb/sr and b = (13.1 +/- 2.1(stat)(-2.7)(+1.0)(syst)) pb/sr. The data are compatible with vanishing p-waves and a sizable d-wave contribution. This finding should strongly constrain the contribution of the A isobar to the dd -> He-4 pi(0) reaction and is, therefore, crucial for a quantitative understanding of quark mass effects in nuclear production reactions.

Place, publisher, year, edition, pages
ELSEVIER SCIENCE BV, 2018
Keywords
Charge symmetry breaking, Deuteron deuteron interactions, Pion production
National Category
Subatomic Physics Astronomy, Astrophysics and Cosmology
Identifiers
urn:nbn:se:uu:diva-358693 (URN)10.1016/j.physletb.2018.04.037 (DOI)000435653100082 ()
Funder
EU, FP7, Seventh Framework Programme, 227431Swedish Research CouncilKnut and Alice Wallenberg Foundation
Available from: 2018-09-05 Created: 2018-09-05 Last updated: 2018-09-05Bibliographically approved
Adlarson, P., Augustyniak, W., Bardan, W., Bashkanov, M., Bergmann, F. S., Berlowski, M., . . . Zurek, M. (2018). Isotensor Dibaryon in the pp -> pp pi(+)pi(-) Reaction?. Physical Review Letters, 121(5), Article ID 052001.
Open this publication in new window or tab >>Isotensor Dibaryon in the pp -> pp pi(+)pi(-) Reaction?
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2018 (English)In: Physical Review Letters, ISSN 0031-9007, E-ISSN 1079-7114, Vol. 121, no 5, article id 052001Article in journal (Refereed) Published
Abstract [en]

Exclusive measurements of the quasifree pp -> pp pi(+)pi(-) reaction have been carried out at WASA@ COSY by means of pd collisions at T-p = 1.2 GeV. Total and differential cross sections have been extracted covering the energy region T-p = 1.08-1.36 GeV, which is the region of N* (1440) and Delta(123)Delta(1232) resonance excitations. Calculations describing these excitations by t-channel meson exchange are at variance with the measured differential cross sections and underpredict substantially the experimental total cross section. An isotensor Delta N dibaryon resonance with I(J(P)) = 2(1(+)) produced associatedly with a pion is able to overcome these deficiencies.

Place, publisher, year, edition, pages
AMER PHYSICAL SOC, 2018
National Category
Subatomic Physics
Identifiers
urn:nbn:se:uu:diva-362841 (URN)10.1103/PhysRevLett.121.052001 (DOI)000440415600003 ()30118290 (PubMedID)
Funder
German Research Foundation (DFG), CL 214/3-2
Available from: 2018-10-15 Created: 2018-10-15 Last updated: 2018-10-15Bibliographically approved
Adlarson, P., Collaboration, W.-a., Augustyniak, W., Bardan, W., Bashkanov, M., Bergmann, F. S., . . . Wirzba, A. (2018). Search for C violation in the decay eta -> pi(0)e(+)e(-) with WASA-at-COSY. Physics Letters B, 784, 378-384
Open this publication in new window or tab >>Search for C violation in the decay eta -> pi(0)e(+)e(-) with WASA-at-COSY
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2018 (English)In: Physics Letters B, ISSN 0370-2693, E-ISSN 1873-2445, Vol. 784, p. 378-384Article in journal (Refereed) Published
Abstract [en]

We report on the search for the rare decay eta -> pi(0)e(+)e(-) which is of interest to study C violation in the electromagnetic interaction which would indicate contributions from physics beyond the Standard Model, since the allowed decay via a two-photon intermediate state is strongly suppressed. The experiment has been performed using the WASA-at-COSY installation, located at the COSY accelerator of the Forschungszentrum Julich, Germany. In total 3 x 10(7) events of the reaction pd -> He-3 eta have been recorded at an excess energy of Q = 59.8MeV. Based on this data set the C parity violating decay eta -> pi(0)gamma* -> pi(0)e(+)e(-) via a single-photon intermediate state has been searched for, resulting in new upper limits of Gamma(eta -> pi(0)e(+) e(-))/Gamma(eta -> pi(+) pi(-) pi(0)) < 3.28 x 10(-5) and Gamma(eta -> pi(0)e(+) e(-))/Gamma(eta -> all)< 7.5 x 10(-6) (CL=90%), respectively. 

Place, publisher, year, edition, pages
ELSEVIER SCIENCE BV, 2018
National Category
Subatomic Physics Astronomy, Astrophysics and Cosmology
Identifiers
urn:nbn:se:uu:diva-368116 (URN)10.1016/j.physletb.2018.07.017 (DOI)000445781600056 ()
Funder
EU, FP7, Seventh Framework Programme, 227431Swedish Research CouncilKnut and Alice Wallenberg Foundation
Available from: 2018-12-06 Created: 2018-12-06 Last updated: 2018-12-06Bibliographically approved
Adlarson, P., Augustyniak, W., Bardan, W., Bashkanov, M., Bass, S. D., Bergmann, F. S., . . . Zurek, M. (2018). Spin Dependence of eta Meson Production in Proton-Proton Collisions Close to Threshold. Physical Review Letters, 120(2), Article ID 022002.
Open this publication in new window or tab >>Spin Dependence of eta Meson Production in Proton-Proton Collisions Close to Threshold
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2018 (English)In: Physical Review Letters, ISSN 0031-9007, E-ISSN 1079-7114, Vol. 120, no 2, article id 022002Article in journal (Refereed) Published
Abstract [en]

Taking advantage of the high acceptance and axial symmetry of the WASA-at-COSY detector, and the high polarization degree of the proton beam of COSY, the reaction →pp→ppη has been measured close to threshold to explore the analyzing power Ay. The angular distribution of Ay is determined with the precision improved by more than 1 order of magnitude with respect to previous results, allowing a first accurate comparison with theoretical predictions. The determined analyzing power is consistent with zero for an excess energy of Q=15  MeV, signaling s-wave production with no evidence for higher partial waves. At Q=72  MeV the data reveal strong interference of Ps and Pp partial waves and cancellation of (Pp)2 and Ss∗Sd contributions. These results rule out the presently available theoretical predictions for the production mechanism of the η meson.

National Category
Subatomic Physics
Identifiers
urn:nbn:se:uu:diva-341490 (URN)10.1103/PhysRevLett.120.022002 (DOI)000419478800004 ()
Available from: 2018-02-21 Created: 2018-02-21 Last updated: 2018-02-21Bibliographically approved
Adlarson, P., Augustyniak, W., Bardan, W., Bashkanov, M., Bergmann, F. S., Berlowski, M., . . . Wilkin, C. (2018). Total and differential cross sections of η-production in proton–deuteron fusion for excess energies between Qη = 13 MeV and Qη = 81 MeV. Physics Letters B, 782, 297-304
Open this publication in new window or tab >>Total and differential cross sections of η-production in proton–deuteron fusion for excess energies between Qη = 13 MeV and Qη = 81 MeV
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2018 (English)In: Physics Letters B, ISSN 0370-2693, E-ISSN 1873-2445, Vol. 782, p. 297-304Article in journal (Refereed) Published
Abstract [en]

New data on both total and differential cross sections of the production of eta mesons in proton-deuteron fusion to He-3 eta in the excess energy region 13.6 MeV <= Q(eta) <= 80.9 MeV are presented. These data have been obtained with the WASA-at-COSY detector setup located at the Forschungszentrum Julich, using a proton beam at 15 different beam momenta between p(p) = 1.60 GeV/c and p(p) = 1.74 GeV/c. While significant structure of the total cross section is observed in the energy region 20 MeV less than or similar to Q(eta) less than or similar to 60 MeV, a previously reported sharp variation around Q(eta) approximate to 50 MeV cannot be confirmed. Angular distributions show the typical forward- peaking that was noted earlier. For the first time, it is possible to study the development of these angular distributions with rising excess energy over a wide interval.

Keywords
Meson production, Proton-deuteron interactions, eta meson
National Category
Subatomic Physics Astronomy, Astrophysics and Cosmology
Identifiers
urn:nbn:se:uu:diva-361529 (URN)10.1016/j.physletb.2018.05.036 (DOI)000438486900050 ()
Funder
EU, FP7, Seventh Framework Programme, 283286German Research Foundation (DFG), GRK2149
Note

WoS title: Total and differential cross sections of eta-production in proton-deuteron fusion for excess energies between Q(eta)=13 MeV and Q(eta)=81 MeV

Available from: 2018-09-25 Created: 2018-09-25 Last updated: 2018-12-21Bibliographically approved
Adlarson, P., Augustyniak, W., Bardan, W., Bashkanov, M., Bergmann, F. S., Berlowski, M., . . . Zurekj, M. (2017). Isoscalar single-pion production in the region of Roper and d*(2380) resonances. Physics Letters B, 774, 599-607
Open this publication in new window or tab >>Isoscalar single-pion production in the region of Roper and d*(2380) resonances
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2017 (English)In: Physics Letters B, ISSN 0370-2693, E-ISSN 1873-2445, Vol. 774, p. 599-607Article in journal (Refereed) Published
Abstract [en]

Exclusive measurements of the quasi-free pn -> pp pi(-) and pp -> pp pi(0) reactions have been performed by means of pd collisions at T-p= 1.2 GeV using the WASA detector setup at COSY. Total and differential cross sections have been obtained covering the energy region T-p= 0.95-1.3 GeV (root s = 2.3-2.46 GeV), which includes the regions of triangle(1232), N*(1440) and d*(2380) resonance excitations. From these measurements the isoscalar single-pion production has been extracted, for which data existed so far only below T-p = 1 GeV. We observe a substantial increase of this cross section around 1 GeV, which can be related to the Roper resonance N*(1440), the strength of which shows up isolated from the triangle resonance in the isoscalar (N pi)(I=0) invariant-mass spectrum. No evidence for a decay of the dibaryon resonance d*(2380) into the isoscalar (NN pi)(I=0) channel is found. An upper limit of 180 mu b (90% CL.) corresponding to a branching ratio of 9% has been deduced.

Place, publisher, year, edition, pages
ELSEVIER SCIENCE BV, 2017
Keywords
Single-pion production, Isoscalar part, Roper resonance, Dibaryon resonance
National Category
Astronomy, Astrophysics and Cosmology
Identifiers
urn:nbn:se:uu:diva-344327 (URN)10.1016/j.physletb.2017.10.015 (DOI)000414973200078 ()
Funder
German Research Foundation (DFG), CL 214/3-1German Research Foundation (DFG), CL 214/3-2
Available from: 2018-03-08 Created: 2018-03-08 Last updated: 2018-03-08Bibliographically approved
Adlarson, P., Augustyniak, W., Bardan, W., Bashkanov, M., Bergmann, F. S., Berlowski, M., . . . Leupold, S. (2017). Measurement of the ω → π+π−π0 Dalitz plot distribution: The WASA-at-COSY Collaboration. Physics Letters B, 770, 418-425
Open this publication in new window or tab >>Measurement of the ω → π+ππ0 Dalitz plot distribution: The WASA-at-COSY Collaboration
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2017 (English)In: Physics Letters B, ISSN 0370-2693, E-ISSN 1873-2445, Vol. 770, p. 418-425Article in journal (Refereed) Published
Abstract [en]

Using the production reactions pd -> He-3 omega and pp -> pp omega, the Dalitz plot distribution for the omega -> pi(+)pi(-)pi(0)decay is studied with the WASA detector at COSY, based on a combined data sample of (4.408 +/- 0.042) x 10(4) events. The Dalitz plot density is parametrised by a product of the P-wave phase space and a polynomial expansion in the normalised polar Dalitz plot variables Z and phi. For the first time, a deviation from pure P-wave phase space is observed with a significance of 4.1 sigma. The deviation is parametrised by a linear term 1+2 alpha Z, with alpha determined to be +0.147 +/- 0.036, consistent with the expectations of rho-meson-type final-state interactions of the P-wave pion pairs. (C) 2017 The Author. Published by Elsevier B.V.

Keywords
Decays of other mesons, Meson-meson interactions, Light mesons
National Category
Astronomy, Astrophysics and Cosmology Subatomic Physics
Identifiers
urn:nbn:se:uu:diva-329932 (URN)10.1016/j.physletb.2017.03.050 (DOI)000404196500054 ()
Funder
Swedish Research CouncilKnut and Alice Wallenberg FoundationEU, FP7, Seventh Framework Programme, 2008-1; 227431
Note

Title in WoS: Measurement of the omega -> pi(+)pi(-)pi(0) Dalitz plot distribution

Available from: 2018-02-06 Created: 2018-02-06 Last updated: 2018-12-20Bibliographically approved
Adlarson, P., Augustyniak, W., Bardan, W., Bashkanov, M., Bergmann, F. S., Berlowski, M., . . . Zurek, M. (2017). Search for eta-mesic He-4 in the dd -> (3)Hen pi(0) and dd -> (3)Hep pi(-) reactions with the WASA-at-COSY facility. Nuclear Physics A, 959, 102-115
Open this publication in new window or tab >>Search for eta-mesic He-4 in the dd -> (3)Hen pi(0) and dd -> (3)Hep pi(-) reactions with the WASA-at-COSY facility
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2017 (English)In: Nuclear Physics A, ISSN 0375-9474, E-ISSN 1873-1554, Vol. 959, p. 102-115Article in journal (Refereed) Published
Abstract [en]

The search for He-4-eta bound states was performed with the WASA-at-COSY facility via the measurement of the excitation function for the dd -> (3)Hen pi(0) and dd -> (3)Hep pi(-) processes. The deuteron beam momentum was varied continuously between 2.127 GeV/c and 2.422 GeV/c, corresponding to the excess energy for the dd -> He-4 eta reaction ranging from Q = 70 MeV to Q = 30 MeV. The luminosity was determined based on the dd -> (3)Hen reaction and the quasi-free proton proton scattering via dd -> ppn(spectator)n(spectator) reactions. The excitation functions, determined independently for the measured reactions, do not reveal a structure which could be interpreted as a narrow mesic nucleus. Therefore, the upper limits of the total cross sections for the bound state production and decay in dd -> (4He-eta)(bound) -> (3)Hen pi(0) and dd -> (He-4-eta)(bound) -> (3)Hep pi(-) processes were determined taking into account the isospin relation between the both of the considered channels. The results of the analysis depend on the assumptions of the N* (1535) momentum distribution in the anticipated mesic-He-4. Assuming, as in the previous works, that this is identical with the distribution of nucleons bound with 20 MeV in He-4, we determined that (for the mesic bound state width in the range from 5 MeV to 50 MeV) the upper limits at 90% confidence level are about 3 nb and about 6 nb for n pi(0) and p pi(-) channels, respectively. However, based on the recent theoretical findings of the N*(1535) momentum distribution in the N*-He-3 nucleus bound by 3.6 MeV, we find that the WASA-at-COSY detector acceptance decreases and hence the corresponding upper limits are 5 nb and 10 nb for n pi(0) and p pi(-) channels respectively. (C) 2017 Elsevier B.V. All rights reserved.

Place, publisher, year, edition, pages
ELSEVIER SCIENCE BV, 2017
Keywords
eta-Mesic nuclei, eta meson
National Category
Subatomic Physics
Identifiers
urn:nbn:se:uu:diva-320871 (URN)10.1016/j.nuclphysa.2017.01.001 (DOI)000395211400007 ()
Funder
EU, European Research Council
Available from: 2017-04-26 Created: 2017-04-26 Last updated: 2017-04-26Bibliographically approved
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