Absolute total cross sections for the charge transfer and dissociative charge transfer channels in the collisions of O+(4S )+H2

Absolute total cross sections for the reactions, O+(4S) + H2(X 1Σ+g)→O+H+2 [reaction (1)] and O+H+H+ [reaction (2)] have been measured in the center-of-mass collision energy (Ec.m.) range of 1.33–22.22 eV. The appearance energies for H+2 (1.70±0.10 eV) and H+ (4.50±0.10 eV) are in excellent agreement with the thermochemical thresholds for reactions (1) and (2), respectively. At Ec.m. higher than approximately 9 eV, the total cross sections for reactions (1) and (2) are greater than that for the exothermic channel forming OH++H.