Investigation of Na 2p⁵3s3p resonances using angular resolved photoelectron spectroscopy of laser-aligned sodium atoms

With a combination of laser and synchrotron radiation the photoionization process of sodium atoms in the region of the autoionizing resonances Na 2p 5 3s3p was investigated. The well defined polarization of both radiation fields was used to prepare the atoms by laser-pumping in aligned valence excited states and study the angular distribution of the photoelectrons which were emitted after the 2p to 3s excitation by synchrotron radiation. An analysis of the angular resolved photoelectron spectra and ab initio calculations for the 2p 5 3s3p resonances are presented.