PRESENT STATUS OF INNER-SHELL PHOTOIONIZATION STUDIES IN SINGLY-CHARGED AND MULTIPLY-CHARGED ATOMIC IONS

Our present knowledge of ionic photoionization is critically reviewed. The inadequacy of theoretical calculations based on the independent-p article model for low- and medium-charge state ions is demonstrated, e mphasizing the need for measurements of total and partial photoionizat ion cross sections in singly- and multiply-charged ions. The experimen tal techniques for obtaining photoabsorption, photoionization, and pho toelectron spectra of ionized species are described and some selected examples are discussed. The perspectives opened up by the use of an EC R ion source in combination with the radiation emitted by undulators o f third-generation storage rings are sketched out.