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arXiv · 1408.0081

Nuclear deformation at finite temperature

Y. Alhassid·C. N. Gilbreth·G. F. Bertsch
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Abstract

Deformation, a key concept in our understanding of heavy nuclei, is based on a mean-field description that breaks the rotational invariance of the nuclear many-body Hamiltonian. We present a method to analyze nuclear deformations at finite temperature in a framework that preserves rotational invariance. The auxiliary-field Monte-Carlo method is used to generate the statistical ensemble and calculate the probability distribution associated with the quadrupole operator. Applying the technique to nuclei in the rare-earth region, we identify model-independent signatures of deformation and find that deformation effects persist to higher temperatures than the spherical-to-deformed shape phase-transition temperature of mean-field theory.

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Y. Alhassid, C. N. Gilbreth, G. F. Bertsch. 2014-08-01. Nuclear deformation at finite temperature. https://doi.org/10.1103/physrevlett.113.262503

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