Channel competition in strong-field dissociation of CS$^+$

ORAL

Abstract

We study intense ultrafast laser-induced dissociation of a CS$^+$ ion beam, utilizing a coincidence 3-D momentum imaging technique. Over a laser intensity range of 10$^{10}$--10$^{16}$ W/cm$^2$, we find clear intensity-dependent behavior of the C$^+$+S and C+S$^+$ branching ratios. Specifically, we observe that the branching ratios are nearly equal at low intensities ($\sim$10$^{10}$--10$^{12}$ W/cm$^2$) and deviate from each other at higher intensities ($>$10$^{13}$ W/cm$^2$), where C+S$^+$ dominates. We propose that the low-intensity branching ratio behavior is due to strong mixing of states corresponding to the relevant dissociation limits mediated by the non-adiabatic couplings, and we identify possible dissociation pathways involving these couplings. Another aspect of channel competition, closing and opening of the two dissociation channels as a function of total energy, is distinctly observed, and this behavior is characterized using the well-known Wigner law for near-threshold behavior [1,2]. \\[4pt] [1] E. P. Wigner, Phys. Rev. \textbf{73}, 1002 (1948).\\[0pt] [2] H. R. Sadeghpour \emph{et al.}, J. Phys. B \textbf{33}, R93 (2000).

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Authors

  • Bethany Jochim

    J. R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, KS USA 66506, J.R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA

  • M. Zohrabi

    J. R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, KS USA 66506, J.R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA, J.R. Macdonald Laboratory, Kansas State University, Manhattan KS 66506

  • K.J. Betsch

    J. R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, KS USA 66506

  • U. Ablikim

    J. R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, KS USA 66506, J.R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA

  • Ben Berry

    Kansas State University, J. R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, KS USA 66506, J.R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, KS 66506, USA

  • T. Severt

    J.R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, KS 66506, USA, J. R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, KS USA 66506, J.R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA

  • A.M. Summers

    Kansas State University, J. R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, KS USA 66506, J.R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA

  • K.D. Carnes

    Kansas State University, J. R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, KS USA 66506, J.R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA

  • B.D. Esry

    Kansas State University, J. R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, KS USA 66506, J.R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA, J. R. Macdonald Laboratory, Kansas State University, Manhattan, KS 66506, USA, J. R. Macdonald Laboratory, Kansas State University, J. R. Macdonald Laboratory, Department of Physics, Kansas State University

  • I. Ben-Itzhak

    Kansas State University, J. R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, KS USA 66506, J.R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA, J.R. Macdonald Laboratory, Kansas State University Manhattan KS 66506 USA, J.R. Macdonald Laboratory, Kansas State University, Manhattan KS 66506