Phys.Rev. C 88, 024307 (2013)

M.Guttormsen, B.Jurado, J.N.Wilson, M.Aiche, L.A.Bernstein, Q.Ducasse, F.Giacoppo, A.Gorgen, F.Gunsing, T.W.Hagen, A.C.Larsen, M.Lebois, B.Leniau, T.Renstrom, S.J.Rose, S.Siem, T.Tornyi, G.M.Tveten, M.Wiedeking

Constant-temperature level densities in the quasicontinuum of Th and U isotopes

NUCLEAR REACTIONS ²³²Th(d, p), (d, d'), (d, t), E=12 MeV; ²³²Th(³He, ³He'), (³He, α), E=24 MeV; ²³⁸U(d, p), (d, d'), (d, t), E=15 MeV; measured (particle)γ-coin in the quasicontinuum region using SiRi particle detector array and CACTUS-γ detector system at Oslo cyclotron laboratory; deduced excitation energy vs Eγ distributions. ^231,232,233Th, ^237,238,239U; deduced level densities using the Oslo method, increase in level density for odd-A isotopes as compared to even-even isotopes, similar temperatures in the quasicontinuum. ^237,238,239U; deduced entropy, excess of entropy for odd-A isotopes as compared to even-even neighbor, microcanonical temperature, heat capacity. Evidence for continuous melting of Cooper pairs from constant temperature behavior.

doi: 10.1103/PhysRevC.88.024307