Two - photon decay in highly charged heavy ions : Spectral shape of the 2 E 1 ( 2 1 S 0 → 1 1 S 0 ) in He - like tin
نویسندگان
چکیده
We have measured the two-photon 2E1 transition from the singlet 1s2s 1S0 to the 1s 1S0 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 1s2s 1S0 → 1s 2 1 S0 (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.
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