The level density and gamma-ray strength function in the quasi-continuum of 238Np has been measured using the Oslo method. The level density function follows closely the constant-temperature level density formula and reaches 43 million levels per MeV at Sn = 5.488 MeV of excitation energy. The gamma-ray strength function displays a two-humped resonance at low-energy as also seen in previous investigations of Th, Pa and U isotopes. The structure is interpreted as the scissors resonance and has an average centroid of wSR = 2.26(5) MeV and a total strength of BSR = 10.8(12)m2N, which is in excellent agreement with sum-rule estimates. The scissors resonance is shown to have an impact on the 237Np(n; g)238Np cross section.
Cite
@article{arxiv.1402.6203,
title = {Level density and gamma-ray strength function in the odd-odd 238Np},
author = {Tamás Gábor Tornyi and Magne Guttormsen and Tomas Kvalheim Eriksen and Andreas Görgen and Francesca Giacoppo and Trine Wiborg Hagen and Attila Krasznahorkay and Ann-Cecilie Larsen and Therese Renstrøm and Sunniva Johanne Rose and Sunniva Siem and Gry Merete Tveten},
journal= {arXiv preprint arXiv:1402.6203},
year = {2014}
}
Comments
arXiv admin note: substantial text overlap with arXiv:1310.7068