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The nuclear moment of inertia and spin distribution of nuclear levels

Y. Alhassid·G. F. Bertsch·L. Fang·S. Liu
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Abstract

We introduce a simple model to calculate the nuclear moment of inertia at finite temperature. This moment of inertia describes the spin distribution of nuclear levels in the framework of the spin-cutoff model. Our model is based on a deformed single-particle Hamiltonian with pairing interaction and takes into account fluctuations in the pairing gap. We derive a formula for the moment of inertia at finite temperature that generalizes the Belyaev formula for zero temperature. We show that a number-parity projection explains the strong odd-even effects observed in shell model Monte Carlo studies of the nuclear moment of inertia in the iron region.

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Y. Alhassid, G. F. Bertsch, L. Fang, S. Liu. 2005-08-13. The nuclear moment of inertia and spin distribution of nuclear levels. https://doi.org/10.1103/physrevc.72.064326

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