ELECTRON-BEAM BOMBARDMENT OF THE CHROMOSPHERE IN A FLARE LOOP WITH ELECTRIC CURRENTS

In a flare loop with electric current and corresponding Ohm electric f ield the electron beam bombardment of chromospheric layers is consider ed. It is assumed that the electric current, which is generated during the slow evolution before a flare, flows along current filaments in t he flare loop and all current densities in these filaments are below a ny thresholds of current instabilities. The convergence of magnetic fi eld below transition region and its influence on current densities in current filaments are considered. The Ohm electric field in the VAL-mo del chromosphere is determined and compared with the electric field eq uivalent to collisional losses of the 30-100 keV electrons at these la yers. It was found that for sufficiently high current densities and el ectron energies the Ohm electric field can be greater than that of col lisional one, mainly at upper chromosphere. Using a numerical model of electron beam bombardment in a flare loop, the energy changes of init ially 100 keV electrons during their penetration into the chromosphere in the case with and without the presence of electric current are com puted. The significance of these effects and their influences on inter pretations of hard X-ray emission and evaporation process are discusse d.