Single and triple differential cross sections for double photoionization of H-

The hydride anion H- would not be bound in the absence of electron correlation. Since the double-photoionization process is exquisitely sensitive to electron correlation, one expects electron correlation effects to leave a strong signature on the double-ionization cross sections for H-. We present fully differential cross sections for the three-body breakup of H- by single-photon absorption. The absolute triply and singly differential cross sections were obtained from ab initio calculations making use of exterior complex scaling within a discrete-variable-representation partial-wave basis. Results calculated at photon energies of 18 and 30 eV are compared with reported cross sections for helium calculated at 20 eV above the double-ionization threshold. These comparisons show a clear signature of initial-state correlations that differentiate the He and H- cases.