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arXiv · 1901.10391

Examination of an isospin-dependent single-nucleon momentum distribution for the isospin-asymmetric nuclear matter in heavy-ion collisions

Gao-Feng Wei·Qi-Jun Zhi·Xin-Wei Cao·Zheng-Wen Long
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Abstract

Within a transport model using as the input nucleon momentum profiles from a parameterized isospin-dependent single-nucleon momentum distribution with a high momentum tail induced by short-range correlations, we employ the $^{197}$Au + $^{197}$Au collisions at 400 MeV/nucleon to examine on one hand effects of the short-range correlations on the pion and flow observables in probing the nuclear symmetry energy, and on the other hand how reliable are this isospin-dependent single-nucleon momentum distribution as well as the corresponding parameter settings. Besides significant effects of the short-range correlations on the pion and flow observables are observed, we also find that the theoretical simulations of $^{197}$Au + $^{197}$Au collisions with this momentum distribution using two sets of parameters extracted from the experimental analysis and the self-consistent Green's function prediction, respectively, can reproduce the neutron elliptic flows of the FOPI-LAND experiment and the $\pi^{-}/\pi^{+}$ ratios of the FOPI experiment under the symmetry energy setting in a certain range. Therefore, we conclude that this parameterized isospin-dependent single-nucleon momentum distribution is reliable for the isospin-asymmetric nuclear matter, correspondingly, two sets of parameters extracted from both the experimental analysis and the self-consistent Green's function prediction can not be ruled out according to the available experimental information at present.

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Gao-Feng Wei, Qi-Jun Zhi, Xin-Wei Cao, Zheng-Wen Long. 2019-01-29. Examination of an isospin-dependent single-nucleon momentum distribution for the isospin-asymmetric nuclear matter in heavy-ion collisions. https://doi.org/10.1007/s41365-020-00779-6

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