Nuclear Excitation by Two-Photon Electron Transition A. V. Volotka, A. Surzhykov, S. Trotsenko, G. Plunien, Th. Stöhlker, and S. Fritzsche
Phys. Rev. Lett. 117, 243001 – Published 5 December 2016 ABSTRACT ( Note: go to site for proper text format) A new mechanism of nuclear excitation via two-photon electron transitions (NETP) is proposed and studied theoretically. As a generic example, detailed calculations are performed for the E1E1 1s2s1S0→1s21S0 two-photon decay of a He-like 225Ac87+ ion with a resonant excitation of the 3/2+ nuclear state with an energy of 40.09(5) keV. The probability for such a two-photon decay via the nuclear excitation is found to be PNETP=3.5×10−9 and, thus, is comparable with other mechanisms, such as nuclear excitation by electron transition and by electron capture. The possibility for the experimental observation of the proposed mechanism is thoroughly discussed. http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.117.243001 Harry
