Nonresonant Two Photon Detachment of the Negative Chlorine Ion.

Michael Scheer, R. C. Bilodeau, Harold K. Haugen

Henrik Stapelfeldt, J O Gaardsted, T. Andersen +1 more

Павел Абрамович Головинский, B. A. Zon

Henrick Stepelfeldt, Péter Balling, Harold K. Haugen

R. C. Bilodeau, Michael Scheer, Harold K. Haugen

The behavior of near-threshold cross sections for dissociation of a target into a pair of particles, as described by Wigner's threshold law, can depend sensitively on the angular momentum of the particles. In this Letter, we investigate the near-threshold nonresonant two-photon detachment process in the negative ion of gold. The expected s-wave threshold behavior is observed with linearly polarized light. Closure of the s-wave channel is realized by using circular polarization, allowing the first observation of a d-wave threshold. Practical applications are discussed, including extensions which could prove valuable for investigations of negative ions with near-threshold structure.

H. W. van der Hart

The R-matrix Floquet approach is applied to study the negative and ions in a light field. Detachment rates are obtained for detachment processes involving up to three photons. The results obtained in the present approach are compared to other experimental and theoretical results. For two- and three-photon processes reasonable agreement with other calculations has been found, while for two-photon detachment the results agree with the experimental cross sections. The three-photon results are in less good agreement with experiment although the larger error bars make accurate comparisons more difficult. The changes in the detachment behaviour for these ions are compared to each other as well as to the detachment behaviour of .