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Isospin effects on rotational flow in intermediate energy heavy ion collisions

Lie-Wen Chen·Feng-Shou Zhang·Zhi-Yuan Zhu
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Abstract

Within the framework of an isospin-dependent quantum molecular dynamics model, the rotational flow in reactions of $^{58}$Fe + $^{58}$Fe and $^{58}$% Ni + $^{58}$Ni at 40 MeV/nucleon for different impact parameters is investigated by analyzing the mid-rapidity azimuthal distribution. The rotational observables are also calculated semiquantitatively. For the first time, it is found that the more neutron-rich system ($^{58}$Fe + $^{58}$Fe) exhibits stronger rotational collective flow. This isospin dependence of rotational collective flow is more appreciable in semi-peripheral collisions and it is shown to mainly result from the isospin dependence of nucleon-nucleon cross section rather than the symmetry energy. Meanwhile, it is indicated that the rotational flow depends strongly on the impact parameter.

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Lie-Wen Chen, Feng-Shou Zhang, Zhi-Yuan Zhu. 2000-11-01. Isospin effects on rotational flow in intermediate energy heavy ion collisions. https://doi.org/10.1103/physrevc.61.067601

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