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arXiv · 0710.2877

Differential isospin-fractionation in dilute asymmetric nuclear matter

Bao-An Li·Lie-Wen Chen·Hong-Ru Ma·Jun Xu·Gao-Chan Yong
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Abstract

The differential isospin-fractionation (IsoF) during the liquid-gas phase transition in dilute asymmetric nuclear matter is studied as a function of nucleon momentum. Within a self-consistent thermal model it is shown that the neutron/proton ratio of the gas phase becomes {\it smaller} than that of the liquid phase for energetic nucleons, although the gas phase is overall more neutron-rich. Clear indications of the differential IsoF consistent with the thermal model predictions are demonstrated within a transport model for heavy-ion reactions. Future comparisons with experimental data will allow us to extract critical information about the momentum dependence of the isovector strong interaction.

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Bao-An Li, Lie-Wen Chen, Hong-Ru Ma, Jun Xu, Gao-Chan Yong. 2007-10-15. Differential isospin-fractionation in dilute asymmetric nuclear matter. https://doi.org/10.1103/physrevc.76.051601

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