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arXiv · 2310.13280

Collective Enhancement of Nuclear Level Density and its fade-out in $^{161}$Dy

T. Santhosh·P. C. Rout·S. Santra·A. Pal·G. Mohanto·Ramandeep Gandhi·A. Baishya
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Abstract

The nuclear level density is a fundamental quantity in nuclear physics, governing various nuclear reactions and astrophysical processes. In this study, we report on the collective enhancement of nuclear level density and its fade-out with excitation energy in the deformed $^{161}$Dy, obtained through an exclusive measurement of neutron evaporation spectra. The $^{162}$Dy nucleus was populated via the transfer of a triton in a $^{7}$Li-induced reaction on $^{159}$Tb. Statistical model analysis of the neutron spectra revealed a large collective enhancement factor of 42$\pm$2, consistent with microscopic calculations. This enhancement factor is similar to the one obtained for mass A$\sim$170 in our previous measurement. The energy-dependent collective enhancement over a wide range of excitation energies was inferred by combining the present results with the available Oslo level density below the neutron binding energy.

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T. Santhosh, P. C. Rout, S. Santra, A. Pal, G. Mohanto, Ramandeep Gandhi, A. Baishya. 2023-10-20. Collective Enhancement of Nuclear Level Density and its fade-out in $^{161}$Dy. https://arxiv.org/abs/2310.13280

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