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Effects of particle-number conservation on heat capacity of nuclei

K. Esashika·H. Nakada·K. Tanabe
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Abstract

By applying the particle-number projection to the finite-temperature BCS theory, the $S$-shaped heat capacity, which has recently been claimed to be a fingerprint of the superfluid-to-normal phase transition in nuclei, is reexamined. It is found that the particle-number (or number-parity) projection gives $S$-shapes in the heat capacity of nuclei which look qualitatively similar to the observed ones. These $S$-shapes are accounted for as effects of the particle-number conservation on the quasiparticle excitations, and occur even when we keep the superfluidity at all temperatures by assuming a constant gap in the BCS theory. The present study illustrates significance of the conservation laws in studying phase transitions of finite systems.

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K. Esashika, H. Nakada, K. Tanabe. 2005-09-14. Effects of particle-number conservation on heat capacity of nuclei. https://doi.org/10.1103/physrevc.72.044303

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