Energy dependence of high resolution integral-collision-cross-section measurements for elastic scattering of H and D atoms by Hg at thermal energies

High resolution measurements of the energy dependence of the integral collision cross section for the elastic scattering of H and D atoms by Hg at thermal energies are presented and the experimental setup described. Evidence for resonant scattering due to quasibound states is obtained. The results are compared with the predictions of a potential obtained from spectroscopic data, after averaging the calculated cross sections over experimental parameters. Modifying the potential in the transition region, between the wall and the long−range part, improves the agreement between the results and the predictions of the spectroscopic potential in the region of the resonance. The new potential also slightly improves the agreement between energy level predictions and spectroscopic data.