[Loops] New paper: Non-equilibrium ionization by a periodic electron beam. I. Synthetic coronal spectra and implications for interpretation of observations

[J. Dudík]

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

-- 
Dr Jaroslav Dudík
research scientist
Astronomical Institute
Czech Academy of Sciences
Fricova 298
251 65 Ondrejov, Czech Republic
tel. 00420 323 620 244