Rotational excitation of methylidynium (CH+) by a helium atom at high temperature

Abstract

We aim to obtain accurate rate coefficients for the collisional excitation of CH+ by He for high gas temperatures. The ab initio coupled-cluster [CCSD(T)] approximation was used to compute the interaction potential energy. Cross sections are then derived in the close coupling (CC) approach and rate coefficients inferred by averaging these cross sections over a Maxwell-Boltzmann distribution of kinetic energies. Cross sections are calculated up to 10'000 cm^-1 for J ranging from 0 to 10. Rate coefficients are obtained at high temperatures up to 2000 K.

4 pages, 3 figures, table with rate coefficients, accepted for publication by A&A

References in corpus (4)

• Models of turbulent dissipation regions in the diffuse interstellar medium
• X-ray chemistry in envelopes around young stellar objects
• Influence of UV radiation from a massive YSO on the chemistry of its envelope
• Modeling of diffuse molecular gas applied to HD 102065 observations

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