Impact of restricted spin-ranges in the Oslo Method: The example of (d,p)${}^{240}\mathrm{Pu}$

Abstract

In this paper we present the first systematic analysis of the impact of the populated vs. intrinsic spin distribution on the nuclear level density and $\gamma$-ray strength function retrieved through the Oslo Method. We illustrate the effect of the spin distribution on the recently performed ${}^{239}\mathrm{Pu}$(d,p$\gamma$)${}^{240}\mathrm{Pu}$ experiment using a 12 MeV deuteron beam performed at the Oslo Cyclotron Lab. In the analysis we couple state-of-the-art calculations for the populated spin-distributions with the Monte-Carlo nuclear decay code RAINIER to compare Oslo Method results to the known input. We find that good knowledge of the populated spin distribution is crucial and show that the populated distribution has a significant impact on the extracted nuclear level density and $\gamma$-ray strength function for the ${}^{239}\mathrm{Pu}$(d,p$\gamma$)${}^{240}\mathrm{Pu}$ case.

arXiv commentPresented at the 6th International Workshop on Compound-Nuclear Reactions and Related Topics

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Cited by in corpus (2)

• Nuclear level densities and $\gamma$-ray strength functions in ${}^{120,124}$Sn isotopes: impact of Porter-Thomas fluctuations
• A new software implementation of the Oslo method with rigorous statistical uncertainty propagation