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Title: Absolute photoionization cross-section measurements of the Kr I isoelectronic sequence

Abstract

Photoionization spectra have been recorded in the 4s, 4p, and 3d resonance regions for the Kr I isoelectronic sequence using both the dual laser produced plasma (DLP) technique (at DCU) to produce photoabsorption spectra, and the merged ion beam and synchrotron radiation technique (at ASTRID) to measure absolute photoionization cross sections. Profile parameters are compared for the 4s-np resonances of Rb{sup +} and Sr{sup 2+}. Many 4p{yields}ns, md transitions are identified with the aid of Hartree-Fock calculations, and consistent quantum defects are observed for the various ns and md Rydberg series. Absolute single and double photoionization cross sections recorded in the 3d region for Rb{sup +} and Sr{sup 2+} ions show preferential decay via double photoionization. This is only the second report to our knowledge where both the DLP technique and the merged-beam technique have been used simultaneously to record photoionization spectra, and the advantages of both techniques (i.e., better resolution in the case of DLP and values for absolute photoionization cross sections in the case of the merged-beam technique) are highlighted.

Authors:
; ; ;  [1]; ;  [2];  [3];  [4];  [5];  [6]
  1. NCPST and The School of Physical Sciences, Dublin City University, Dublin (Ireland)
  2. Institute of Physics and Astronomy, University of Aarhus, DK-8000 Aarhus C (Denmark)
  3. LIXAM, Universite Paris Sud, Orsay 91405 (France)
  4. School of Mathematics and Physics, Queen's University of Belfast, Belfast BT7 1NN (United Kingdom)
  5. Department of Physics, University College Cork, Cork (Ireland)
  6. Daresbury Laboratory, Warrington WA4 4AD (United Kingdom)
Publication Date:
OSTI Identifier:
20982331
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 75; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevA.75.032711; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; CATIONS; CROSS SECTIONS; DECAY; DEFECTS; HARTREE-FOCK METHOD; ION BEAMS; KRYPTON; LASER-PRODUCED PLASMA; PHOTOIONIZATION; PHOTON-ATOM COLLISIONS; RESOLUTION; RESONANCE; RUBIDIUM; RUBIDIUM IONS; RYDBERG STATES; SPECTRA; STRONTIUM; STRONTIUM IONS; SYNCHROTRON RADIATION

Citation Formats

Kilbane, D., Banahan, C., Kampen, P. van, Costello, J. T., Folkmann, F., Kjeldsen, H., Bizau, J.-M., Scully, S., Mansfield, M. W. D., and West, J. B.. Absolute photoionization cross-section measurements of the Kr I isoelectronic sequence. United States: N. p., 2007. Web. doi:10.1103/PHYSREVA.75.032711.
Kilbane, D., Banahan, C., Kampen, P. van, Costello, J. T., Folkmann, F., Kjeldsen, H., Bizau, J.-M., Scully, S., Mansfield, M. W. D., & West, J. B.. Absolute photoionization cross-section measurements of the Kr I isoelectronic sequence. United States. doi:10.1103/PHYSREVA.75.032711.
Kilbane, D., Banahan, C., Kampen, P. van, Costello, J. T., Folkmann, F., Kjeldsen, H., Bizau, J.-M., Scully, S., Mansfield, M. W. D., and West, J. B.. Thu . "Absolute photoionization cross-section measurements of the Kr I isoelectronic sequence". United States. doi:10.1103/PHYSREVA.75.032711.
@article{osti_20982331,
title = {Absolute photoionization cross-section measurements of the Kr I isoelectronic sequence},
author = {Kilbane, D. and Banahan, C. and Kampen, P. van and Costello, J. T. and Folkmann, F. and Kjeldsen, H. and Bizau, J.-M. and Scully, S. and Mansfield, M. W. D. and West, J. B.},
abstractNote = {Photoionization spectra have been recorded in the 4s, 4p, and 3d resonance regions for the Kr I isoelectronic sequence using both the dual laser produced plasma (DLP) technique (at DCU) to produce photoabsorption spectra, and the merged ion beam and synchrotron radiation technique (at ASTRID) to measure absolute photoionization cross sections. Profile parameters are compared for the 4s-np resonances of Rb{sup +} and Sr{sup 2+}. Many 4p{yields}ns, md transitions are identified with the aid of Hartree-Fock calculations, and consistent quantum defects are observed for the various ns and md Rydberg series. Absolute single and double photoionization cross sections recorded in the 3d region for Rb{sup +} and Sr{sup 2+} ions show preferential decay via double photoionization. This is only the second report to our knowledge where both the DLP technique and the merged-beam technique have been used simultaneously to record photoionization spectra, and the advantages of both techniques (i.e., better resolution in the case of DLP and values for absolute photoionization cross sections in the case of the merged-beam technique) are highlighted.},
doi = {10.1103/PHYSREVA.75.032711},
journal = {Physical Review. A},
number = 3,
volume = 75,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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