Electron capture in H++H2

Electron capture in H++H2 collisions is studied at energies of 1.0, 2.0, and 3.0 keV in the reduced angular range tau< or =3.0 keV deg. Time-of-flight techniques are used for state identification, and the probability of electron capture to H(1s)+H2+( 2Σ/sub g/ ) in an exchange collision is determined. This is shown to be the dominant exchange channel at small scattering angles. The ''summed'' exchange channels have a reduced cross section that is found to peak in the forward direction and shows no structure, while the cross section for capture to final ground-state channels shows some small structure at 3.0 keV for tau> or =1.5 keV deg. The reduced cross section, at 1.0 keV, for capture to excited states of H (with the H2+ in its ground state) is found to have a maximum at tau = 1 keV deg. The results are in agreement with a previously proposed model for ion-molecule charge exchange