Photoionization of laser-excited Caesium atoms above the 4d ionization threshold

The photoionization of the ground state and 6p laser-excited caesium atoms was studied above their 4d ionization thresholds. The 4d photoelectron spectrum of 6p laser-excited atoms shows a stronger excitation of satellites upon ionization than its ground state counterpart. The relative intensities of satellite and main photolines show a slow variation with the incoming photon energy for both the ground state and the 6p laser-excited states. An assignment of the excited state spectra, supported by recently published ground state photoionization spectra and calculations, is given and a preliminary analysis of the 4d Auger spectrum of laser-excited atoms is also presented.