Non-relativistic Free-Free Emission due to the n-distribution of Electrons—Radiative Cooling and Thermally Averaged and Total Gaunt Factors
Abstract
Tracking the thermal evolution of plasmas, characterized by an n-distribution, using numerical simulations, requires the determination of the emission spectra and of the radiative losses due to free-free emission from the corresponding temperature-averaged and total Gaunt factors. Detailed calculations of the latter are presented and associated with n-distributed electrons with the parameter n ranging from 1 (corresponding to the Maxwell-Boltzmann distribution) to 100. The temperature-averaged and total Gaunt factors with decreasing n tend toward those obtained with the Maxwell-Boltzmann distribution. Radiative losses due to free-free emission in a plasma evolving under collisional ionization equilibrium conditions and composed by H, He, C, N, O, Ne, Mg, Si, S, and Fe ions, are presented. These losses decrease with a decrease in the parameter n, reaching a minimum when n = 1, and thus converge with the loss of thermal plasma. Tables of the thermal-averaged and total Gaunt factors calculated for n-distributions, and a wide range of electron and photon energies, are presented.
- Publication:
-
The Astrophysical Journal Supplement Series
- Pub Date:
- September 2017
- DOI:
- 10.3847/1538-4365/aa850a
- arXiv:
- arXiv:1707.05291
- Bibcode:
- 2017ApJS..232...12D
- Keywords:
-
- atomic data;
- atomic processes;
- ISM: general;
- plasmas;
- radio continuum: general;
- radiation mechanisms: general;
- Astrophysics - High Energy Astrophysical Phenomena
- E-Print:
- Accepted for publication in ApJS. 70 pages, 7 figures and 11 tables