Super-allowed α decay above doubly-magic 100Sn and properties of 104Te = 100Sn ⊗ α

Abstract

α-decay half-lives for 104, 105, 106Te and 108, 109, 110Xe close above the doubly-magic 100Sn are calculated from systematic double-folding potentials. The derived α preformation factors are compared to results for 212, 213, 214Po and 216, 217, 218Rn above the doubly-magic 208Pb. α-decay energies of Q α = 5.42±0.07MeV and 4.65±0.15MeV are predicted for 104Te and 108Xe; the corresponding half-lives are T 1/2 ≈ 5ns for 104Te and of the order of 60μs for 108Xe. Additionally, the properties of rotational bands in 104Te are analyzed, and the first excited 2+ state in 104Te is predicted at E x = 650±40keV; it decays preferentially by γ emission with a reduced transition strength of 10 Weisskopf units to the ground state of 104Te and with a minor branch by α emission to the ground state of 100Sn.