Efficient computation of collisional $\ell$-mixing rate coefficients in astrophysical plasmas

Abstract

We present analytical expressions for direct evaluation of $\ell$-mixing rate coefficients in proton-excited hydrogen atom collisions and describe a software package for efficient numerical evaluation of the collisional rate coefficients. Comparisons between rate coefficients calculated with various levels of approximation are discussed, highlighting their range of validity. These rate coefficients are benchmarked via radio recombination lines for hydrogen, evaluating the corresponding departure coefficients from local thermal equilibrium.

References in corpus (5)

• Carbon and hydrogen radio recombination lines from the cold clouds towards Cassiopeia A
• Low Frequency Carbon Radio Recombination Lines I: Calculations of Departure Coefficients
• Emission and recombination coefficients for hydrogen with kappa-distributed electron energies
• H, He-like recombination spectra II: $l$-changing collisions for He Rydberg states
• On the treatment of $\ell$-changing proton-hydrogen Rydberg atom collisions

Cited by in corpus (1)

• H, He-like recombination spectra IV; H, He-like recombination spectra IV: clarification and refinement of methodology for $l$-changing collisions