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arXiv · 1905.13461

Nuclear level densities and gamma-ray strength functions in samarium isotopes

F. Naqvi·A. Simon·M. Guttormsen·R. Schwengner·S. Frauendorf·C. S. Reingold·J. T. Burke·N. Cooper·R. O. Hughes·S. Ota·A. Saastamoinen
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Abstract

The gamma-strength functions and level densities in the quasi-continuum of 147;149Sm isotopes have been extracted from particle-coincidences using the Oslo method. The nuclei of interest were populated via (p,d) reactions on pure 148;150Sm targets and the reaction products were recorded by the Hyperion array. An upbend in the low-energy region of the gSF has been observed. The systematic analysis of the gSF for a range of Sm isotopes highlights the interplay between scissors mode and the upbend. Shell-model calculations show reasonable agreement with the experimental gSFs and confirm the correspondence between the upbend and scissors mode.

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F. Naqvi, A. Simon, M. Guttormsen, R. Schwengner, S. Frauendorf, C. S. Reingold, J. T. Burke, N. Cooper, R. O. Hughes, S. Ota, A. Saastamoinen. 2019-05-31. Nuclear level densities and gamma-ray strength functions in samarium isotopes. https://doi.org/10.1103/physrevc.99.054331

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