2017/06/06 by Carla Maria Coppola, C. M. Coppola, M. V. Kazandjian +4
Chemistry · Physics and Astronomy · #Astrochemistry #Astronomy #Astrophysics #Astrophysics and Star Formation Studies #Atomic physics #Chemistry #Cosmology and Gravitation Theories #Dark Matter and Cosmic Phenomena #Helium #Hydrogen #Interstellar medium #Molecule #Photochemistry #Photodissociation #Photon #Physics #Quantum mechanics #Radiative transfer #Thermal #Thermodynamics #Universe #astro-ph.CO #astro-ph.GA
paper · pdf · doi:10.1093/mnras/stx1397
6 pages, 4 figures, 1 table; accepted for publication on MNRAS
openalex publication_date 2017/06/06 · arxiv created 2017/06/07 · arxiv updated 2017/08/02 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Non-thermal photons deriving from radiative transitions among the internal ladder of atoms and molecules are an important source of photons in addition to thermal and stellar sources in many astrophysical environments. In the present work, the calculation of reaction rates for the direct photodissociation of some molecules relevant in early Universe chemistry is presented; in particular, the calculations include non-thermal photons deriving from the recombination of primordial hydrogen and helium atoms for the cases of H2, HD and HeH+. New effects on the fractional abundances of chemical species are investigated and the fits for the HeH+ photodissociation rates by thermal photons are provided.