LOW-ENERGY-ELECTRON CAPTURE FROM H AND D BY C3+ IONS

We have computed cross sections for charge transfer between C3+(1s(2)2 s S-2) and H(1s S-2) for relative collision energies in the range 0.00 4 less than or equal to E less than or equal to 90 eV amu(-1). The mol ecular orbital data were taken from Errea et al (1991a); both triplet and singlet spin symmetries were considered. In order to extend the ca lculations to low energies, where the rate coefficient is required for astrophysical applications, a quantal treatment of the molecular dyna mics was adopted. Comparison is made with previous calculations and wi th experiment, including the recent measurements of Havener et al (199 5). At low energies, cross sections for electron capture from deuteriu m are found to be significantly smaller than the corresponding ones fo r hydrogen owing to the dynamical effect of the greater reduced mass.