Collisional excitation and decay of the 1P shape resonance of H-

The 1P shape resonance of H- has been populated in collisions between H- and Xe. We report on the decay: H-( 1P)→H0(n 2)+e-, which for the first time is measured by high-resolution electron spectroscopy. New information on the angular distribution of ejected electrons is obtained by use of a Shore parametrization to describe the cross section. The Shore parameters are related to matrix elements of the transition operator. The obtained resonance energy and width are in good agreement with recent theoretical calculations as well as other experimental results