Single electron detachment from H- by proton impact

We are concerned with the basic single electron detachment process H++H-→H++H(1s)+e at incident velocities v ranging from the threshold 0.235 au to 10 au. It has been known for more than two decades, that the eikonal Coulomb-Born (ECB) approximation of Gayet, Janev and Salin is in disagreement, by two-three orders of magnitude, with the experiment of Peart, Grey and Dolder. Moreover, the total cross sections of the ECB method tend to a constant value at large incident velocities v, in sharp contrast with the corresponding proper Bethe asymptote v-2 ln v2. This is unexpected since the ECB model properly includes the long-range Coulombic effects in both the entrance and exit channels. We reinvestigated the problem and found that the initial scattering state in the ECB model is inconsistent with the perturbation potential which causes the transition in the ''prior'' form of the T-matrix. When this basic deficiency of the theory is removed, a novel method called the modified Coulomb-Born (MCB) approximation emerges, which is found to be in good agreement with the measurements. (orig.)