By means of a crossed-beams technique we have measured absolute cross
sections for the charge-transfer reaction C3+ + He2+ --> C4+ + He+ by
coincident detection of the product ions C4+ and He+ for CM energies b
etween 4 and 200 keV. Estimates of angular differential cross sections
are made from measured scattering distributions of He+ reaction produ
cts at CM energies of 5.15 and 15.86 keV. The total cross sections for
charge transfer are calculated by close coupling of a two-centre atom
ic basis.