Electron-impact rotational excitation of the carbon monosulphide (CS) molecule
Résumé
Rotational excitation of the carbon monosulphide (CS) molecule by thermal electron-impact is studied using the molecular forumla-matrix method combined with the adiabatic-nuclei-rotation (ANR) approximation. Rate coefficients are obtained for electron temperatures in the range 5–5000 K and for transitions involving levels up to J= 40. It is confirmed that dipole allowed transitions (ΔJ= 1) are dominant and that the corresponding rate coefficients exceed those for excitation by neutrals by at least five orders of magnitude. As a result, the present rates should be included in any detailed population model of CS in sources where the electron fraction is larger than ∼10−5, in particular in diffuse molecular clouds and interstellar shocks.
Domaines
Planète et Univers [physics]Origine | Fichiers éditeurs autorisés sur une archive ouverte |
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