Wave-function collapse with increasing ionization: 4dphotoabsorption of Cs throughCs4+

A. Cummings, C. McGuinness, G. O'Sullivan, J. T. Costello, J. P. Mosnier, E. T. Kennedy
2001 Physical Review A. Atomic, Molecular, and Optical Physics  
The 4d relative photoabsorption cross section of cesium has been observed to change dramatically in appearance along the isonuclear sequence Cs through Cs 4ϩ . In each case, discrete structure is observed below threshold and for Cs through Cs 2ϩ , a giant dipole 4d→ f resonance is also present above threshold. Between Cs 2ϩ and Cs 3ϩ , there is a striking change, with much of the oscillator strength available in the 4d→ f channel being abruptly transferred to the discrete spectrum. Despite the
more » ... ctrum. Despite the complexity of the transitions involved, the oscillator strength envelope for the discrete transitions yields relatively few features and remains essentially static in energy regardless of the parent terms. Hartree-Fock with configuration interaction and time-dependent local-density-approximation calculations successfully account for this behavior and permit identification of the discrete features.
doi:10.1103/physreva.63.022702 fatcat:wfnuhgmd4fb3nkf7pbng5oeyee