Generation of energetic electrons at the termination shock during solar flares - RHESSI observations

G. Mann

H. Aurass, and A. Warmuth

During solar flares in the solar corona magnetic field energy is converted by reconnection in plasma heating, mass motions, energetic particles, and electromagnetic radiation. The magnetic reconnection process is accompanied by a strong outflow of plasma from the reconnection site. If this flow becomes super-Alfvenic a so-called termination shock can be established in the outflow region. The solar event on July 18, 2002 shows signatures of such a termination shock in the solar radio radiation about 300 MHz. The X-ray data of the RHESSI satellite reveal a strong correlation of the hard X-ray pulses with the occurrence of this termination shock. The energetic electrons producing the hard X-ray radiation are regarded to be generated by the termination shock via shock drift acceleration. The theoretically obtained energetic electron fluxes are compared with the RHESSI data.