Signatures of the non-Maxwellian κ-distributions in optically thin line spectra I. Theory and synthetic Fe IX–XIII spectra

0435318 - ASÚ 2015 RIV FR eng J - Journal Article
Dudík, J. - Del Zanna, G. - Mason, H. E. - Dzifčáková, Elena
Signatures of the non-Maxwellian κ-distributions in optically thin line spectra I. Theory and synthetic Fe IX–XIII spectra.
Astronomy & Astrophysics. Roč. 570, October (2014), A124/1-A124/23. ISSN 0004-6361. E-ISSN 1432-0746
R&D Projects: GA ČR GAP209/12/1652
Institutional support: RVO:67985815
Keywords : Sun: UV radiation * X-rays * gamma rays
Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics
Impact factor: 4.378, year: 2014

We investigate the possibility of diagnosing the degree of departure from the Maxwellian distribution using single-ion spectra originating in astrophysical plasmas in collisional ionization equilibrium. We find that it is possible to perform density diagnostics independently of kappa, with many Fe xi, Fe xii, and Fe xiii line ratios showing strong density-sensitivity and negligible sensitivity to kappa and temperature. We also tested different averaging of the collision strengths. It is found that averaging over 0.01 interval in log(E [ Ryd ]) is sufficient to produce accurate distribution-averaged collision strengths Upsilon(T,kappa) at temperatures of the ion formation in ionization equilibrium.
Permanent Link: http://hdl.handle.net/11104/0239182