Phys.Rev. C 106, 014302 (2022)

M.Si, R.Lozeva, H.Naidja, A.Blanc, J.-M.Daugas, F.Didierjean, G.Duchene, U.Koster, T.Kurtukian-Nieto, F.Le Blanc, P.Mutti, M.Ramdhane, W.Urban

New β-decay spectroscopy of the ¹³⁷Te nucleus

RADIOACTIVITY ¹³⁷Te(β^-), (β^-n)[from ²³⁵U(n, F), E=thermal at the high flux reactor of Institut Laue-Langevin (ILL), followed by separation of fragments using LOHENGRIN separator]; measured Eγ, Iγ, γγ-coin, βγ-coin using two clover Ge detectors surrounded by BGO anti-Compton shields, and a coaxial HPGe detector for γ radiation, and plastic scintillators for β radiation. ¹³⁷I; deduced levels, J, π, β feedings, logft, shell-model configurations and wave function amplitudes. ¹³⁶I; deduced one level at 87.3 keV through the observation of g.s. transition. ¹³⁷Te; measured T_1/2 of its decay by time distribution of β-decay events; estimated lower limit of %β^-n or P_n decay mode. Comparison of level structure of ¹³⁷I with theoretical shell-model (SM) calculations.

doi: 10.1103/PhysRevC.106.014302