Two-photon decay in highly charged heavy ions: Spectral shape of the 2E1 (2 1S0 -> 1 1S0) in He-like tin

A. Kumar (1) , Sergiy Trotsenko (1) , A. V. Volotka (2) , D. Banas , H.F. Beyer (1) , Harald Bräuning (1) , Sephan Fritzsche (1) , Alexander Gumberidze (1) , S. Hagmann (1) , S. Hess (1) , Christophor Kozhuharov (1) , G. Plunien , Regina Reuschl (1) , Uwe Spillmann (1) , Martino Trassinelli (1, 3) , G. Weber (1) , Thomas Stöhlker (1)

1 GSI - Helmholtz zentrum für Schwerionenforschung GmbH
2 USP - Department of Physics
3 INSP - Institut des Nanosciences de Paris

We have measured the two-photon 2E1 transition from the singlet 1s2s 1S0 to the 1s21S0 ground state of helium-like tin. The experiment was performed by using initially Li-like tin ions in collision with a nitrogen gas target at the ESR storage ring at the energy of 300 MeV/u. The two-photon emission arises from the decay of the exclusively formed 1s2s states following the ionization of one K-shell electron from the Li-like ions. The obtained spectral shape of the 1s2s1S0 - 1s21S0 (2E1) transition was compared with the one calculated within a relativistic approach. The spectral shape is displayed and its sensitivity with regard to details in the theoretical description of the 2E1 decay is discussed.

Domaines: Physique Atomique [physics.atom-ph]

A. Kumar, Sergiy Trotsenko, A. V. Volotka, D. Banas, H.F. Beyer, et al.. Two-photon decay in highly charged heavy ions: Spectral shape of the 2E1 (2 1S0 -> 1 1S0) in He-like tin. Journal of Physics: Conference Series, 2009, 163 (1), pp.012027. ⟨10.1088/1742-6596/163/1/012027⟩. ⟨hal-00430921⟩