EMPIRICAL DETERMINATION OF THE ENERGY LOSS RATE OF ACCELERATED ELECTRONS IN A WELL-OBSERVED SOLAR FLARE

We present electron images of an extended solar flare source, deduced from RHESSI hard X-ray imaging spectroscopy data. We apply the electron continuity equation to these maps in order to determine empirically the form of the energy loss rate for the bremsstrahlung-emitting electrons. We show that this form is consistent with an energy transport model involving Coulomb collisions in a target with a temperature of about 2 x 107 K, with a continuous injection of fresh deka-keV electrons at a rate of approximately 10-2 electrons s-1 per ambient electron.