Strong Dynamical Effects in the X-Ray Photoemission Spectra and X-Ray Emission Spectra of the Elements Pd to Xe

Many-electron interactions within one atomic shell can cause a breakdown of the quasi-particle picture of a core hole by causing strong fluctuations. Typical examples are 4s and 4p XPS spectra and Lγ2,3(L1N2,3) X-ray emission spectra of the elements 46Pd to 54Xe. In these cases quasiparticle picture of 4p core hole breaks down due to very strong dynamical dipolar fluctuations and associated decay processes of the 4p core hole. The theory presented agrees well with experimental data.