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Expansion and evaporation of hot nuclei: Comparison between semi-classical and quantal mean-field approaches

D. Lacroix·Ph. Chomaz
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Abstract

We present a general discussion of the mean field dynamics of finite nuclei prepared under extreme conditions of temperature and pressure. We compare the prediction of semi-classical approximation with complete quantum simulations. Many features of the dynamics are carefully studied such as the collective expansion, the evaporation process, the different time-scale... This study points out many quantitative differences between quantum and semi-classical approaches. Part of the differences are related to numerical features inherent in semi-classical simulations but most of them are a direct consequence of the non treatment of nuclei as quantal objects. In particular, we show that because of a too strong damping in semi-classical approaches the expansion of hot nuclei is quenched and the speed of the collective motion reduced.

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D. Lacroix, Ph. Chomaz. 1998-10-01. Expansion and evaporation of hot nuclei: Comparison between semi-classical and quantal mean-field approaches. https://doi.org/10.1016/s0375-9474(98)00203-6

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