Nuclear interlevel transfer driven by collective outer shell electron oscillation

We discuss the possibility of exploiting the dynamic electron-nucleus interaction in order to form a nuclear population inversion in a short-lifetime excited state. We first review the situation in terms of dynamic hyperfine mixing between the nucleus and electron single-particle states. Then we treat the subject of nonlinear collective electron motion. We present results for the calculation of electron photoabsorption cross sections by the time-dependent Thomas-Fermi-Dirac-Weizsacker method1 as well as for the coupling of the resulting electron excitations to the nucleus. We also discuss the problem of premature ionization of the atoms involved.