Autoionization dynamics of excited collision systems: Angular dependence of the electron and ion energy spectra forHe*(23S)+H

We present the first angle-dependent energy spectra for the basic autoionization process ${\mathrm{He}}^{\mathrm{*}}$($2^3$S)+H($1^2$S) leading to Penning ionization (→He+${\mathrm{H}}^{+}$+${\mathit{e}}^{\mathrm{-}}$; PI) and associative ionization [→${\mathrm{HeH}}^{+}$(${\mathit{v}}^{+}$,${\mathit{J}}^{+}$)+${\mathit{e}}^{\mathrm{-}}$; AI]. Our results include electron energy spectra for both reaction channels and the ${\mathrm{H}}^{+}$-ion energy spectra for PI. The variation of the electron spectra with angle demonstrates the presence of substantial contributions from non-s-type electron partial waves, with the angle-dependent electron signals due to AI yielding clear information on the internal electron angular distribution of the autoionizing quasimolecule.