%0 Journal Article
%T Electron-impact excitation of diatomic hydride cations II: OH+ and SH+
%+ Institut de Planétologie et d'Astrophysique de Grenoble (IPAG)
%A Hamilton, James R.
%A Faure, Alexandre
%A Tennyson, Jonathan
%< avec comité de lecture
%@ 0035-8711
%J Monthly Notices of the Royal Astronomical Society
%I Oxford University Press (OUP): Policy P - Oxford Open Option A
%V 476
%P 2931-2937
%8 2018
%D 2018
%Z 1802.07566
%Z 2018MNRAS.476.2931H
%R 10.1093/mnras/sty437
%K line: formation
%K molecular data
%K molecular processes
%K ISM: molecules
%K Astrophysics - Solar and Stellar Astrophysics
%K Astrophysics - Astrophysics of Galaxies
%Z Sciences of the Universe [physics]
%Z Sciences of the Universe [physics]/Astrophysics [astro-ph]Journal articles
%X R-matrix calculations combined with the adiabatic-nuclei-rotation and Coulomb-Born approximations are used to compute electron-impact rotational rate coefficients for two open-shell diatomic cations of astrophysical interest: the hydoxyl and sulphanyl ions, OH+ and SH+. Hyperfine resolved rate coefficients are deduced using the infinite-order-sudden approximation. The propensity rule ΔF = Δj = ΔN = ±1 is observed, as is expected for cations with a large dipole moment. A model for OH+ excitation in the Orion Bar photon-dominated region is presented which nicely reproduces Herschel observations for an electron fraction xe = 10-4 and an OH+ column density of 3 × 1013 cm-2. Electron-impact electronic excitation cross-sections and rate coefficients for the ions are also presented.
%G English
%2 https://insu.hal.science/insu-03693559/document
%2 https://insu.hal.science/insu-03693559/file/sty437.pdf
%L insu-03693559
%U https://insu.hal.science/insu-03693559
%~ INSU
%~ UNIV-SAVOIE
%~ UGA
%~ CNRS
%~ INPG
%~ IRSTEA
%~ CNES
%~ OSUG
%~ IPAG
%~ AGREENIUM
%~ INRAE
%~ UGA-COMUE
%~ USMB-COMUE