uu.seUppsala University Publications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Electron Dynamics Within the Electron Diffusion Region of Asymmetric Reconnection
Univ New Hampshire, Ctr Space Sci, Durham, NH USA.ORCID iD: 0000-0001-6315-1613
Univ New Hampshire, Ctr Space Sci, Durham, NH USA.ORCID iD: 0000-0002-5699-090X
Univ New Hampshire, Ctr Space Sci, Durham, NH USA.ORCID iD: 0000-0001-6997-7037
NASA, Goddard Space Flight Ctr, Greenbelt, MD USA.ORCID iD: 0000-0001-7088-1059
Show others and affiliations
2018 (English)In: Journal of Geophysical Research - Space Physics, ISSN 2169-9380, E-ISSN 2169-9402, Vol. 123, no 1, p. 146-162Article in journal (Refereed) Published
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.

Place, publisher, year, edition, pages
2018. Vol. 123, no 1, p. 146-162
National Category
Fusion, Plasma and Space Physics
Identifiers
URN: urn:nbn:se:uu:diva-348788DOI: 10.1002/2017JA024524ISI: 000425637600012OAI: oai:DiVA.org:uu-348788DiVA, id: diva2:1200554
Available from: 2018-04-24 Created: 2018-04-24 Last updated: 2018-04-24Bibliographically approved

Open Access in DiVA

fulltext(4547 kB)6 downloads
File information
File name FULLTEXT01.pdfFile size 4547 kBChecksum SHA-512
b3532f9879c572e00409dc0acc73a4bfc6ee217fce440eca9c57bd0c06ab30013b72b2216610161fc183eac22a3574653f49a092496115fa4669d06aa48fc425
Type fulltextMimetype application/pdf

Other links

Publisher's full text

Authority records BETA

Khotyaintsev, Yuri V.

Search in DiVA

By author/editor
Argall, M. R.Paulson, K.Alm, L.Rager, A.Shuster, J.Wang, S.Torbert, R. B.Dors, I.Chutter, M.Farrugia, C.Burch, J.Pollock, C.Giles, B.Gershman, D.Lavraud, B.Russell, C. T.Strangeway, R.Magnes, W.Lindqvist, P. -AKhotyaintsev, Yuri V.Ergun, R. E.Ahmadi, N.
By organisation
Swedish Institute of Space Physics, Uppsala Division
In the same journal
Journal of Geophysical Research - Space Physics
Fusion, Plasma and Space Physics

Search outside of DiVA

GoogleGoogle Scholar
Total: 6 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 54 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf