Fokker-planck description of electron beams in the solar chromosphere

MAUAS, PABLO J. D.; GÓMEZ, DANIEL O.

ASTROPHYSICAL JOURNAL

IOP PUBLISHING LTD

Año: 1997 vol. 483 p. 496 - 506

0004-637X

We numerically solve the relativistic Fokker-Planck equation for a beam of accelerated electrons impinging on the solar chromosphere, for several cases relevant to solar flares. We make a detailed comparison between our results and those obtained from the test-particle approach. We find that the inclusion of velocity diffusion changes significantly not only the resulting distribution function but also macroscopic quantities like the energy deposition rate and the hard X-ray emission. We find that the beam energy is deposited in a deeper and much broader region of the atmosphere. Also, our computations predict a harder and larger hard X-ray emission. These results might be relevant to the long-standing controversy between the thermal and the nonthermal models for the X-ray production, as well as to the study of the acceleration mechanisms of electron beams. © 1997. The American Astronomical Society. All rights reserved.