Ro-vibrational excitation of CS by He
LERMA and UMR 8112 of CNRS, Observatoire de Paris-Meudon, 92195 Meudon Cedex, France e-mail: email@example.com
Accepted: 12 October 2006
Context.Over the next few years, ALMA and Herschel missions will perform high spatial and spectral resolution studies at infrared and sub-millimeter wavelengths. Modeling of the spectra will require accurate radiative and collisional rates for species of astrophysical interest.
Aims.The present paper focuses on the calculation of ro-vibrational excitation rate coefficients of CS by He, useful for studies of high-temperature interstellar environments.
Methods.A new accurate three dimensional (3D) potential energy surface for the CS-He system, which explicitly takes into account the r-dependence of the CS vibration, was calculated. The dynamic calculations were performed using the VCC-IOS approximation.
Results.Cross sections among the 38 first rotational levels of , and are calculated for total energies up to 10 000 cm-1. Rate coefficients between the ro-vibrational levels are calculated for temperatures from 300 K to 1500 K.
Key words: ISM: molecules / molecular data / molecular processes
© ESO, 2007