Analytical formulae for the inverse bremsstrahlung absorption coefficient

Abstract

Simple analytical expressions for calculating the electron-ion, free-free Gaunt factor for high electron temperatures (>or=1eV/k) and long wavelengths (>or=0.1 mu m) are presented. The values of the Gaunt factor are displayed in a graphical form for wavelengths in the range 0.1-100 mu m.