1 / 29

Energetic electrons in collisionless magnetic reconnection

Energetic electrons in collisionless magnetic reconnection. Quanming Lu( 陆全明 ). Department of Geophysics and Planetary Sciences, University of Science and Technology of China, Hefei, China 中国科学技术大学 地球物理和行星科学技术系 CO-WORKERS Rongsheng Wang( 王荣生 ), Xiangrong Fu( 傅向荣 )

bell
Download Presentation

Energetic electrons in collisionless magnetic reconnection

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Energeticelectrons in collisionless magneticreconnection Quanming Lu(陆全明) DepartmentofGeophysicsandPlanetarySciences, UniversityofScienceandTechnologyofChina, Hefei, China 中国科学技术大学 地球物理和行星科学技术系 CO-WORKERS RongshengWang(王荣生),Xiangrong Fu(傅向荣) CanHuang(黄灿), ShuiWang(王水）

  2. 1. Quanming Lu, C. Huang, J. L. Xie, R. S. Wang, M. Y. Wu, A. Vaivads, and S. Wang, J. Geophys. Res., 115, A11208, 2010.2. Wang, R. S., Quanming Lu, X. Li, C. Huang, and S. Wang, J. Geophys. Res., 115, A11201, ,2010.3. Wang, R. S., Quanming Lu, Aiming Du, and Shui Wang, Phys. Rev. Lett., 104, 175003, 2010.4. Wang, R. S., Quanming Lu, C. Huang, and S. Wang, J. Geophys. Res., 115, A01209, 2010.5. Fu, X. R., Quanming Lu and S. Wang, Phys. Plasmas,13, 012309, 2006.

  3. Magnetic reconnection Magnetic reconnection rapidly converts magnetic energy into plasma energy, which leads to heating and acceleration of ions and electrons. Many phenomena are thought to be related with electron dynamics.

  4. Collisionless magnetic reconnection Ion diffusion region: electrons are magnetized while ions are not. Ions and electrons are decoupled. Electron diffusion region: electrons are unmagnetized. Hall current system: quadrupole magnetic field.

  5. (a) Electron flow vector, (b) Ion flow vector, from PIC simulations

  6. (a) Electron parallel current, (b) Electron perpendicular current, (c) Ion parallel current, (d) ion perpendicular current, (e) total parallel current, (f) total perpendicular current, based on PIC simulations

  7. The time evolution of (a) the kinetic energy, (b) , (c) ,(d) without a guide field [Fu et al., PoP, 2006].

  8. 2001.9.10 Clusterinthe magnetotail~ -16 RE [Wang et al., JGR, 2010]

  9. Electron angle distribution near the X line

  10. Electron angle distribution in the outflow region Above the separatrix (g point) the distribution is isotropic for all energy levels. Near the separatrix (h point) electrons with lower energies stream into the X line while electrons with higher energy flow away from the X line. The satellites approach the center of the current sheet, the energy range for field-aligned bidirectional distribution becomes smaller.

  11. （a) Quadrupole structures of the out-of-plane magnetic field , and (b) electron density based on PIC simulations

  12. Electron density and out-of-plane magnetic field based on PIC simulation [Lu et al., JGR, 2010]

  13. Location of Cluster The structure of the ion diffusion region [Vaivads et al., PRL, 2004]

  14. Electron density and out-of-plane magnetic field based on Cluster observations [Lu et al., JGR, 2010].

  15. The effects of the guide field Contour of for

  16. Contour of the electron density for

  17. Electron and ion velocity for

  18. The time evolution of (a) the kinetic energy, (b) , (c) ,(d) with guide field.

  19. Electron parallel current for

  20. Secondary islands in reconnection Open Boundary conditions. In diffusion region, secondary islands are formed and the ejected. [Daughton et al. PoP, 2007]

  21. S>1000, secondary islands are formed in the current sheet. [Daughton et al., PRL 2009]

  22. 2003.10.4, 06:19 UT，Cluster in Magnetotail ~16RE

  23. An reconnection event with a secondary island . [Wang et al. PRL, 2010 ]

  24. The electron parallel and perpendicular temperatures, the differential energetic electron fluxes from C4.

  25. Summary Single X line: No guide field At the edge of the outflow region, there is a high speed electron stream directed away from the X line and a low-speed stream directed toward the X line, which forms the in-plane current. Electron density depletion layers are formed along the separatrices. Therefore, the electron density depletion layers are outside the peaks of the out-of-plane magnetic field, which is verified by both PIC simulations and Cluster observations. With guide field Electron density depletion layers along the lower left and upper right separatrices disappear, and the maximum amplitude of the out-of-plane magnetic field is found in the center of the current sheet.

  26. Secondary island A secondary island is identified in the center of the ion diffusion region by Cluster observations, which possess energetic electron with higher energy .

  27. Thank you!

More Related