Calculation of rate constants for vibrational and rotational excitation of the H3 ion by electron impact
نویسندگان
چکیده
We present theoretical thermally averaged rate constants for vibrational and rotational (de-)excitation of the H3 ion by electron impact. The constants are calculated using the multichannel quantum-defect approach. The calculation includes processes that involve a change | J | ≤ 2 in the rotational angular momentum J of H3 . The rate constants are calculated for states with J ≤ 5 for rotational transitions of the H3 ground vibrational level. The thermal rates for transitions among the lowest eight vibrational levels are also presented, averaged over the rotational structure of the vibrational levels. The conditions for producing non-thermal rotational and vibrational distributions of H3 in astrophysical environments are discussed.
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