Photoelectron spectra of shake-up processes from the 2p subshell of sodium atoms in the excited states 2p63p

The 2p photoionization of sodium atoms from the initial states 2p63p1/2,3/2 have been investigated, with special emphasis placed on the relaxation and correlation effects. To understand the details of the spectra, a series of ab initio calculations based on the multi-configuration Dirac-Fock method have been performed. Theoretical predictions have been compared with the high-resolution spectra measured using a synchrotron radiation source, and suitable agreement between experiment and theory has enabled the identification of fine-structure spectra. The prominent influence of the relaxation and correlation effects on the photoelectron spectra has been analysed according to the detailed calculations.