2020MNRAS.492.3794Z

Radiative association of an oxygen atom with a carbon cation is investigated using quantal and semiclassical methods. The total rate coefficient for spontaneous radiative association of O(2s22p4, 3P) with C+(2s22p, 2P) on the doublet manifold is determined from the corresponding cross-sections. The cross-sections for the 1^2 Σ ^-= A^2Π, 2^2 Σ ^-= A^2Π, and C^2 [?] = A^2Π continuum-bound processes are calculated either semiclassically, in combination with the Breit-Wigner approach, or fully quantum mechanically. In the temperature range 10-10 000 K, our recommended total rate coefficient, obtained from these calculations and the data of Zamecnikova et al. (2019), slowly increases from 7.5 x 10-18 cm3s-1 to 2.1 x 10-17 cm3s-1. Corresponding aspects of the CO+ and CO formations in SN 1987A are discussed.