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Volumetric intensity dependence on the formation of molecular and atomic ions within a high intensity laser focus

  • Lynne Robson
  • Kenneth W. D. Ledingham
  • Paul McKenna
  • Thomas McCanny
  • Seiji Shimizu
  • Jiamin M. Yang
  • Claes-Göran Wahlström
  • Rodrigo Lopez-Martens
  • Katalin Varju
  • Per Johnsson
  • Johan Mauritsson
Articles

Abstract

The mechanism of atomic and molecular ionization in intense, ultra-short laser fields is a subject which continues to receive considerable attention. An inherent difficulty with techniques involving the tight focus of a laser beam is the continuous distribution of intensities contained within the focus, which can vary over several orders of magnitude. The present study adopts time of flight mass spectrometry coupled with a high intensity (8 × 1015 Wcm−2), ultra-short (20 fs) pulse laser in order to investigate the ionization and dissociation of the aromatic molecule benzene-d1 (C6H5D) as a function of intensity within a focused laser beam, by scanning the laser focus in the direction of propagation, while detecting ions produced only in a “thin” slice (400 and 800 µm) of the focus. The resultant TOF mass spectra varies significantly, highlighting the dependence on the range of specific intensities accessed and their volumetric weightings on the ionization/dissociation pathways accessed.

Keywords

Laser Focus Coulomb Explosion Rayleigh Range Volumetric Weighting Extraction Aperture 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© American Society for Mass Spectrometry 2004

Authors and Affiliations

  • Lynne Robson
    • 1
  • Kenneth W. D. Ledingham
    • 1
    • 2
  • Paul McKenna
    • 1
  • Thomas McCanny
    • 1
  • Seiji Shimizu
    • 1
  • Jiamin M. Yang
    • 1
  • Claes-Göran Wahlström
    • 3
  • Rodrigo Lopez-Martens
    • 3
  • Katalin Varju
    • 3
  • Per Johnsson
    • 3
  • Johan Mauritsson
    • 3
  1. 1.Department of PhysicsUniversity of StrathclydeGlasgowUK
  2. 2.AWE plcReadingUK
  3. 3.Department of PhysicsLund Institute of TechnologyLundSweden

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