Rotational quenching of H2CO by molecular hydrogen: cross-sections, rates and pressure broadening
نویسندگان
چکیده
We compute the rotational quenching rates of the first 81 rotational levels of orthoand paraH2CO in collision with orthoand para-H2, for a temperature range of 10–300 K. We make use of the quantum close-coupling and coupled-state scattering methods combined with the high accuracy potential energy surface of Troscompt et al. Rates are significantly different from the scaled rates of H2CO in collision with He; consequently, critical densities are notably lower. We compare a full close-coupling computation of pressure broadening cross-sections with experimental data and show that our results are compatible with the low-temperature measurements of Mengel & De Lucia, for a spin temperature of H2 around 50 K.
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