Numerical study of a propagating nonthermal microwave feature in a solar flare loop

作者：Minoshima T^*; Yokoyama T

来源：Astrophysical Journal, 2008, 686(1): 701-708.

DOI：10.1086/591268

• acceleration of particles
• Sun : flares
• Sun : radio radiation

We study the motion of electrons along a magnetic loop analytically and numerically, and compare the results with observations of the propagating feature of the nonthermal microwave source in the 1999 August 28 solar flare reported by Yokoyama et al. We model the electron motion with the Fokker-Planck equation and calculate the spatial distribution of the gyrosynchrotron radiation. We find that the microwave-propagating feature does not correspond to the motion of electrons with a specific initial pitch angle. This apparent propagating feature is a consequence of the motion of an ensemble of electrons with different initial pitch angles, which have different times and positions, producing strong radiation in the loop. We conclude that the nonthermal electrons in the 1999 August 28 flare were isotropically accelerated and then were injected into the loop.

• 出版日期2008-10-10