Nuclear level densities and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>γ</mml:mi></mml:math>-ray strength functions in samarium isotopes

Abstract

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