Accurate determination of the free-free Gaunt factor. II - relativistic Gaunt factors

Abstract

When modelling an ionised plasma, all spectral synthesis codes need the thermally averaged free-free Gaunt factor defined over a very wide range of parameter space in order to produce an accurate prediction for the spectrum. Until now no data set exists that would meet these needs completely. We have therefore produced a table of relativistic Gaunt factors over a much wider range of parameter space than has ever been produced before. We present tables of the thermally averaged Gaunt factor covering the range log10(gamma^2) = -6 to 10 and log10(u) = -16 to 13 for all atomic numbers Z = 1 through 36. The data were calculated using the relativistic Bethe-Heitler-Elwert (BHE) approximation and were subsequently merged with accurate non-relativistic results in those parts of the parameter space where the BHE approximation is not valid. These data will be incorporated in the next major release of the spectral synthesis code Cloudy. We also produced tables of the frequency integrated Gaunt factor covering the parameter space log10(gamma^2) = -6 to 10 for all values of Z between 1 and 36. All the data presented in this paper are available online.

8 pages, 8 figures, 2 tables

References in corpus (2)

• The 2013 Release of Cloudy
• Accurate determination of the free-free Gaunt factor; I - non-relativistic Gaunt factors

Cited by in corpus (13)

• Stellar limits on scalars from electron-nucleus bremsstrahlung
• Improved calculations of electron-ion Bremsstrahlung Gaunt factors for astrophysical applications
• Bremsstrahlung in GRMHD models of accreting black holes
• Gyroresonance and free-free radio emissions from multi-thermal multi-component plasma
• A magnetic white-dwarf accretion model for the anomalous X-ray pulsar 4U 0142+61
• Platform for Probing Radiation Transport Properties of Hydrogen at Conditions Found in the Deep Interiors of Red Dwarfs
• The physical and chemical structure of Sagittarius B2 VIIIa. Dust and ionized gas contributions to the full molecular line survey of 47 hot cores
• X-ray Spectra from Plasmas with High-Energy Electrons: kappa-distributions and e-e Bremsstrahlung
• New radiative loss curve from updates to collisional excitation in the low-density, optically thin plasmas in SPEX
• Bremsstrahlung Radiation Power in Fusion Plasmas Revisited: Towards Accurate Analytical Fitting
• Investigating the origin of radio emission in candidate super-Eddington accreting black holes
• Effects of radiative losses on the relativistic jets of high-mass microquasars
• Non-relativistic electron-ion bremsstrahlung: an approximate formula for all parameters