J. I. Sakai

Laboratory for Plasma Astrophysics, Faculty of Engineering, Toyama University, 3190, Gofuku, Toyama 930-8555 Japan

We present the results of proton acceleration near an X-type magnetic reconnection region by numerical simulations. The magnetic field is taken to be hyperbolic and time stationary with a uniform electric field perpendicular to the magnetic field. We also study the effects of the magnetic field along the uniform electric field. We found from many parametric runs that the energy spectrum of accelerated protons near an X-type magnetic reconnection region is universal with a power-law spectrum E^-S , where the power-law index S is about 2.0-2.2. The acceleration time of protons with the energy range of 1-20 MeV is very rapid and within ~10²w_ci^-1 which is much less than 1 s for solar flare plasmas. We also present the results of proton acceleration during of two current loops. By using the data of electromagnetic fields obtained from 3-D MHD simulations with different loop configurations, we calculate the orbits of many test protons to obtain the energy spectrum.

Reference

Mori, K., Sakai, J.I. and Zhao, J. (1998) Ap. J. 494, 430.