RCCCIVC~ 30 November i981 Cross SCC~IOIIS for charge cvchangc from ground-state H by Be, B and C nuclcl, m the energy range O-1-50 cV/amu, hJve been calculated by a fully quantaI, pcrturbcd statlonxy state method. A gcncr;llisPtlon is mtroduccd to treat colhslons \i?th fcw-clectron Ions and apphcd to capture by C4+ and C". Results agree wth avadablc mcasuremcnts. Charge exchange IS a dominant recombination mechanism m plasmas whenever sufficient neutral hydrogen is present. Low-energy charge capture reactions are important III determining the ionization balaxe, and the transport properties of neutral and sonic species from the plasma edge mward [I]. Few capture cross sections are reliably known for slow (say, O-500 eV/amu) collisions. Experiments in this range are technically difficult, reqmring new techniques such as laser-plasma ion sources [2] and ton traps [3,4] which access the energy regimes LO-500 and O-10 eV/amu, respectively. Results from merged ion-neutral beam experiments may be expected in the future 1.51.
Theorettcal techmques must also be carefully developed to obtain rehable results at low energies. Classical trajectory results appear to be adequate above several keV/amu while impact parameter perturbed stattonary state (PSS) calculations can be exl Research sponsored Jomtly by the US Department ol Energy, Dwwon of Basic Energy Sciences and the Office of runon Energy under Contract No. W-7405_cng-26 wrth Umon Carbide Corpontlon.