Electron distribution functions in the diffusion region of asymmetric magnetic reconnection. Issue 5 (7th March 2016)

• Record Type: Journal Article
• Authors: Bessho, N.; Chen, L.‐J.; Hesse, M.
• Is Part Of: Geophysical research letters. Volume 43:Issue 5(2016)
• Page Start: 1828
• Page End: 1836
• Publication Date: 2016-03-07
• Subjects: magnetic reconnection -- asymmetric reconnection -- electron distribution function -- PIC simulation -- stagnation point -- diffusion region; Geophysics -- Periodicals; Planets -- Periodicals; Lunar geology -- Periodicals; 550
• DOI: 10.1002/2016GL067886
• Languages: English
• ISSNs: 0094-8276

Abstract

Abstract: We study electron distribution functions in a diffusion region of antiparallel asymmetric reconnection by means of particle‐in‐cell simulations and analytical theory. At the electron stagnation point, the electron distribution comprises a crescent‐shaped population and a core component. The crescent‐shaped distribution is due to electrons coming from the magnetosheath toward the stagnation point and accelerated mainly by electric field normal to the current sheet. Only a part of magnetosheath electrons can reach the stagnation point and form the crescent‐shaped distribution that has a boundary of a parabolic curve. The penetration length of magnetosheath electrons into the magnetosphere is derived. We expect that satellite observations can detect crescent‐shaped electron distributions during magnetopause reconnection. Key Points: Meandering electrons accelerated by the normal electric field determine a crescent distribution Crescent‐shaped populations exist near the electron stagnation point and in the outflow region The distance of penetration into the magnetosphere by magnetosheath electrons is derived