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Elliptic flow in heavy ion collisions near the balance energy

Yu-Ming Zheng·C. M. Ko·Bao-An Li·Bin Zhang
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Abstract

The proton elliptic flow in collisions of Ca on Ca at energies from 30 to 100 MeV/nucleon is studied in an isospin-dependent transport model. With increasing incident energy, the elliptic flow shows a transition from positive to negative flow. Its magnitude depends on both the nuclear equation of state (EOS) and the nucleon-nucleon scattering cross section. Different elliptic flows are obtained for a stiff EOS with free nucleon-nucleon cross sections and a soft EOS with reduced nucleon-nucleon cross sections, although both lead to vanishing in-plane transverse flow at the same balance energy. The study of both in-plane and elliptic flows at intermediate energies thus provides a means to extract simultaneously the information on the nuclear equation of state and the nucleon-nucleon scattering cross section in medium.

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Yu-Ming Zheng, C. M. Ko, Bao-An Li, Bin Zhang. 1999-06-24. Elliptic flow in heavy ion collisions near the balance energy. https://doi.org/10.1103/physrevlett.83.2534

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