The Electron Affinity of Indium and the Fine Structure of In$^{-}$ Measured using Infrared Photodetachment Threshold Spectroscopy

POSTER

Abstract

The binding energies of the fine structure levels of the indium negative ion (In$^{-})$ have been measured using infrared photodetachment threshold spectroscopy. The relative cross section for neutral atom production was measured with a crossed ion-beam-laser-beam apparatus over selected photon energy ranges between 300 -- 670 meV. An $s$-wave threshold was observed due to the opening of the In$^{-}$ (5$p^{2} \quad ^{3}P_{0})$ to In (5$p$ $^{2}P_{1/2})$ ground-state to ground-state transition, yielding an accurate value for the electron affinity of In. Thresholds were also observed for detachment from the J=1 and J=2 excited fine structure levels of In$^{-}$, permitting accurate determination of the fine structure splittings of the negative ion.

Authors

  • C.W. Walter

  • J.A. Summers

    Duke University Medical Physics Graduate Program, Southwest Research Institute, Kettering University, Department of Physics and Astronomy, Wayne State University, Wayne State University, University of Nebraska, University of Stockholm, University of Michigan-Dearborn, Wayne State University, Detroit, MI, Cornell Univ., Air Force Research Labs, Univ. Akron, National Center for Manufacturing Sciences (NCMS), Youngstown State U, Dept. Physics, Department of Natural Sciences, University of Michigan-Dearborn, Department of Physics and Astronomy, Wayne State University, Detroit, Bhabha Atomic Research Centre, Hyderabad, India, NIST Center for Neutron Research, NIST, Gaithersburg, Maryland, Max Planck Institute for Solid State Research, Michigan State University

  • J.A. Summers

    Duke University Medical Physics Graduate Program, Southwest Research Institute, Kettering University, Department of Physics and Astronomy, Wayne State University, Wayne State University, University of Nebraska, University of Stockholm, University of Michigan-Dearborn, Wayne State University, Detroit, MI, Cornell Univ., Air Force Research Labs, Univ. Akron, National Center for Manufacturing Sciences (NCMS), Youngstown State U, Dept. Physics, Department of Natural Sciences, University of Michigan-Dearborn, Department of Physics and Astronomy, Wayne State University, Detroit, Bhabha Atomic Research Centre, Hyderabad, India, NIST Center for Neutron Research, NIST, Gaithersburg, Maryland, Max Planck Institute for Solid State Research, Michigan State University

  • J.A. Summers

    Duke University Medical Physics Graduate Program, Southwest Research Institute, Kettering University, Department of Physics and Astronomy, Wayne State University, Wayne State University, University of Nebraska, University of Stockholm, University of Michigan-Dearborn, Wayne State University, Detroit, MI, Cornell Univ., Air Force Research Labs, Univ. Akron, National Center for Manufacturing Sciences (NCMS), Youngstown State U, Dept. Physics, Department of Natural Sciences, University of Michigan-Dearborn, Department of Physics and Astronomy, Wayne State University, Detroit, Bhabha Atomic Research Centre, Hyderabad, India, NIST Center for Neutron Research, NIST, Gaithersburg, Maryland, Max Planck Institute for Solid State Research, Michigan State University

  • N.D. Gibson

    Denison University