Dear all,
attached please find a link for our new paper "Non-equilibrium ionization by a periodic electron beam I. Synthetic coronal spectra and implications for interpretation of observations" by E Dzifcakova, J Dudik, and S Mackovjak
http://arxiv.org/abs/1603.04256
Abstract We investigate the effects of a periodic high-energy electron beam on the synthetic spectra of coronal Fe ions. Initially, the coronal plasma is assumed to be Maxwellian with a temperature of 1 MK. The high-energy beam, described by a κ-distribution, is then switched on every period P for the duration of P/2. The periods are on the order of several tens of seconds, similar to exposure times or cadences of space-borne spectrometers. Ionization, recombination, and excitation rates for the respective distributions are used to calculate the resulting non-equilibrium ionization state of Fe and the instantaneous and period-averaged synthetic spectra. Under the presence of the periodic electron beam, the plasma is out of ionization equilibrium at all times. The resulting spec- tra averaged over one period are almost always multithermal if interpreted in terms of ionization equilibrium for either a Maxwellian or a κ-distribution. Exceptions occur, however; the EM-loci curves appear to have a nearly isothermal crossing-point for some values of κ_s . The instantaneous spectra show fast changes in intensities of some lines, especially those formed outside of the peak of the respective EM(T ) distributions if the ionization equilibrium is assumed.
My best regards, Jaro
loops@solar.physics.montana.edu