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arXiv · 1511.06840

Stochastic Estimation of Nuclear Level Density in the Nuclear Shell Model: An Application to Parity-Dependent Level Density in $^{58}$Ni

Noritaka Shimizu·Yutaka Utsuno·Yasunori Futamura·Tetsuya Sakurai·Takahiro Mizusaki·Takaharu Otsuka
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Abstract

We introduce a novel method to obtain level densities in large-scale shell-model calculations. Our method is a stochastic estimation of eigenvalue count based on a shifted Krylov-subspace method, which enables us to obtain level densities of huge Hamiltonian matrices. This framework leads to a successful description of both low-lying spectroscopy and the experimentally observed equilibration of $J^π=2^+$ and $2^-$ states in $^{58}$Ni in a unified manner.

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Noritaka Shimizu, Yutaka Utsuno, Yasunori Futamura, Tetsuya Sakurai, Takahiro Mizusaki, Takaharu Otsuka. 2015-12-18. Stochastic Estimation of Nuclear Level Density in the Nuclear Shell Model: An Application to Parity-Dependent Level Density in $^{58}$Ni. https://doi.org/10.1016/j.physletb.2015.12.005

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