Measurements of Total Cross Sections of the n=2 Excitation of Helium from the Impact of 10-25 keV Protons

ORAL

Abstract

Absolute, total cross sections of the n=2 excitation of helium by intermediate-energy proton impact are measured using the energy-loss experimental technique. The incident proton beam is accelerated to kinetic energies of 10-25 keV, and is focused into a target cell containing helium gas at room temperature. A hemispherical energy analyzer is used to measure the energy-loss spectra of the incident and scattered proton beams. The excitation cross sections are determined by measuring the amplitudes of the energy-loss peaks corresponding to excitation of the n=2 states of helium. These measurements are compared to theoretical results, including the First Born, Distortion, Glauber, VPS, and Multi-State Impact Parameter Approximation methods. The calculations that incorporate many-state calculation methods such as the Multi-State Impact Parameter Approximation are in reasonable agreement with the present data, suggesting that strong coupling between states must be considered in intermediate-energy, multi-electron ion-target collision systems.

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Authors

  • Perry Yaney

    Department of Physics, University of Oregon, USAF Research Laboratory, Materials and Manufacturing Directorate, Wright-Patterson AFB, Ohio, NHMFL, CRIEPI, UCSD, University of Dayton, L-3 Communications Cincinnati Electronics, University of Georgia, Air Force Research Laboratory, Anteon Corporation, California State University-Chico, The Ohio State University, Univ. Akron, Air Force Institute of Technology, Albion College, Albion, MI 49224, Physics Department, University of Florida, Gainesville, Mound Laser \& Photonics Center, Inc., Hitachi Global Storage Technologies, San Jose, CA 95120, University of Dayton Research Institute, University of South Alabama, Jet Propulsion Laboratory, Anteon, Universidad Michoacana de San Nicolas de Hidalgo, Morelia, Michoac\'{a}n, Mexico, Department of Chemistry, The University of Akron, Department of Physics, The University of Akron, Physics Department and The Future-Chips Constellation, Renssalaer Polytechnic Institute, Local Co-Chair

  • Perry Yaney

    Department of Physics, University of Oregon, USAF Research Laboratory, Materials and Manufacturing Directorate, Wright-Patterson AFB, Ohio, NHMFL, CRIEPI, UCSD, University of Dayton, L-3 Communications Cincinnati Electronics, University of Georgia, Air Force Research Laboratory, Anteon Corporation, California State University-Chico, The Ohio State University, Univ. Akron, Air Force Institute of Technology, Albion College, Albion, MI 49224, Physics Department, University of Florida, Gainesville, Mound Laser \& Photonics Center, Inc., Hitachi Global Storage Technologies, San Jose, CA 95120, University of Dayton Research Institute, University of South Alabama, Jet Propulsion Laboratory, Anteon, Universidad Michoacana de San Nicolas de Hidalgo, Morelia, Michoac\'{a}n, Mexico, Department of Chemistry, The University of Akron, Department of Physics, The University of Akron, Physics Department and The Future-Chips Constellation, Renssalaer Polytechnic Institute, Local Co-Chair

  • Perry Yaney

    Department of Physics, University of Oregon, USAF Research Laboratory, Materials and Manufacturing Directorate, Wright-Patterson AFB, Ohio, NHMFL, CRIEPI, UCSD, University of Dayton, L-3 Communications Cincinnati Electronics, University of Georgia, Air Force Research Laboratory, Anteon Corporation, California State University-Chico, The Ohio State University, Univ. Akron, Air Force Institute of Technology, Albion College, Albion, MI 49224, Physics Department, University of Florida, Gainesville, Mound Laser \& Photonics Center, Inc., Hitachi Global Storage Technologies, San Jose, CA 95120, University of Dayton Research Institute, University of South Alabama, Jet Propulsion Laboratory, Anteon, Universidad Michoacana de San Nicolas de Hidalgo, Morelia, Michoac\'{a}n, Mexico, Department of Chemistry, The University of Akron, Department of Physics, The University of Akron, Physics Department and The Future-Chips Constellation, Renssalaer Polytechnic Institute, Local Co-Chair

  • T.J. Kvale

    University of Toledo, Toledo, OH 43606

  • Perry Yaney

    Department of Physics, University of Oregon, USAF Research Laboratory, Materials and Manufacturing Directorate, Wright-Patterson AFB, Ohio, NHMFL, CRIEPI, UCSD, University of Dayton, L-3 Communications Cincinnati Electronics, University of Georgia, Air Force Research Laboratory, Anteon Corporation, California State University-Chico, The Ohio State University, Univ. Akron, Air Force Institute of Technology, Albion College, Albion, MI 49224, Physics Department, University of Florida, Gainesville, Mound Laser \& Photonics Center, Inc., Hitachi Global Storage Technologies, San Jose, CA 95120, University of Dayton Research Institute, University of South Alabama, Jet Propulsion Laboratory, Anteon, Universidad Michoacana de San Nicolas de Hidalgo, Morelia, Michoac\'{a}n, Mexico, Department of Chemistry, The University of Akron, Department of Physics, The University of Akron, Physics Department and The Future-Chips Constellation, Renssalaer Polytechnic Institute, Local Co-Chair