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arXiv · 0909.2010

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

K. Hammami·L. C. Owono Owono·P. Staeuber
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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.

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K. Hammami, L. C. Owono Owono, P. Staeuber. 2009-09-10. Rotational excitation of methylidynium (CH+) by a helium atom at high temperature. https://doi.org/10.1051/0004-6361/200912663

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