<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Surzhykov, A.</style></author><author><style face="normal" font="default" size="100%">Indelicato, P.</style></author><author><style face="normal" font="default" size="100%">Santos, J. P.</style></author><author><style face="normal" font="default" size="100%">Amaro, P</style></author><author><style face="normal" font="default" size="100%">Stöhlker, Th</style></author><author><style face="normal" font="default" size="100%">Fritzsche, S.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Two-photon absorption of few-electron heavy ions</style></title><secondary-title><style face="normal" font="default" size="100%">Physical Review A</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">PACS: 32.90.+a, 32.80.Rm, 32.80.Wr, 31.10.+z</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2011</style></year></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://link.aps.org/doi/10.1103/PhysRevA.84.022511</style></url></web-urls></urls><publisher><style face="normal" font="default" size="100%">American Physical Society</style></publisher><volume><style face="normal" font="default" size="100%">84</style></volume><pages><style face="normal" font="default" size="100%">022511</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The two-photon absorption of few-electron ions has been studied by using second-order perturbation theory and Dirac's relativistic equation. Within this framework, the general expressions for the excitation cross sections and rates are derived including a full account of the higher-order multipole terms in the expansion of the electron-photon interaction. While these expressions can be applied to any ion, independent of its particular shell structure, detailed computations are carried out for the two-photon absorption of hydrogen-, helium-, and berylliumlike ions and are compared with the available theoretical and experimental data. The importance of relativistic and nondipole effects in the analysis and computation of induced two-photon transitions is pointed out. Moreover, we discuss the potential of these transitions for atomic parity-violation studies in the high-Z domain.</style></abstract><notes><style face="normal" font="default" size="100%">Copyright (C) 2010 The American Physical SocietyPlease report any problems to prola@aps.orgPRA</style></notes></record></records></xml>