Thermal and Nonthermal Electron Energy Gain in Macroscale Magnetic Reconnection
Abstract
The first self-consistent simulations of electron acceleration duringmagnetic reconnection in a macroscale system are presented. Consistentwith solar flare observations the spectra of energetic electrons takethe form of power-laws that extend more than two decades inenergy. The drive mechanism for these nonthermal electrons is Fermireflection in growing and merging magnetic flux ropes. A strong guidefield suppresses the production of nonthermal electrons byweakening the Fermi drive mechanism. For a weak guide field the totalenergy content of nonthermal electrons dominates that of the hotthermal electrons even though their number density remains small. Ourresults are benchmarked with the hard x-ray, radio and extremeultra-violet (EUV) observations of the X8.2-class solar flare onSeptember 10, 2017. Additionally, recent simulations suggest that the parallel electric field resulting from large scale gradients in the electron pressure and bound the reconnection exhausts is sufficient to produce the energy gain of hot thermal electrons during flare energy release.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2021
- Bibcode:
- 2021AGUFMSH22B..01A