Hyperfine excitation of 13CCH and C13CH by collisions with para-H2

Authors:
Publisher website
Google Scholar
Abstract
The computation of hyperfine resolved cross sections and rate coefficients for open-shell molecules in collision with H2 is a true methodological and numerical challenge. Such collisional data are however required to interpret astrophysical observations. We report the first hyperfine resolved rate coefficients for (de-)excitation of 13CCH and C13CH isotopologues induced by collisions with para-H2. These calculations have been performed using a recently published C2H–H2 potential energy surface. Hyperfine resolved cross sections and rate coefficients between the first 98 energy levels of the two isotopologues were determined using a recoupling technique for temperatures ranging from 5 to 100 K. Significant isotopic substitution effects were found, showing the necessity of computing isotopologue specific collisional data. These rate coefficents have then been used in a simple radiative transfer modeling for typical molecular cloud conditions.
Funding Information
  • European Research Council (811363)

This publication has 41 references indexed in Scilit: