Non-relativistic Free–Free Emission due to the n-distribution of Electrons—Radiative Cooling and Thermally Averaged and Total Gaunt Factors

• Autor(a) principal: de Avillez, Miguel
• Data de Publicação: 2017
• Outros Autores: Breitschwerdt, Dieter
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10174/22784; https://doi.org/10.3847/1538-4365/aa850a
• topic: atomic data; atomic processes; ISM: general; plasmas; radio continuum: general; radiation mechanisms: general; Bremssthralung

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.