On Photoionization in the Hard X-Ray Region

Abstract

It is demonstrated that recent experiments on ionization of 3p and 3s electrons in Ni film and solid body cannot be described in the frames of Hartree-Fock or the random phase approximation with exchange. The deviation is so big that from the theoretical side it requires inclusion of huge and yet not entirely understood effects. Perhaps, it requires also experimental efforts in order to clarify the prominent difference obtained for films and crystal samples.