Nucleon effective mass splitting and density-dependent symmetry energy effects on elliptic flow in heavy ion collisions at E lab = 0.09 ~ 1.5 GeV/nucleon

• Published in: Chinese physics C Vol. 44; no. 7; p. 74103
• Main Authors: Tong, Luyao, Li, Pengcheng, Li, Fupeng, Wang, Yongjia, Li, Qingfeng, Liu, Fanxin
• Format: Journal Article
• Language: English
• Published: 01.07.2020
• ISSN: 1674-1137; 2058-6132
• DOI: 10.1088/1674-1137/44/7/074103

Abstract By incorporating an isospin-dependent form of the momentum-dependent potential in the ultra-relativistic quantum molecular dynamics (UrQMD) model, we systematically investigate effects of the neutron-proton effective mass splitting = and the density-dependent nuclear symmetry energy on the elliptic flow in + collisions at beam energies from 0.09 to 1.5 GeV/nucleon. It is found that at higher beam energies ( 0.25 GeV nucleon) with the approximately 75 MeV difference in slopes of the two different , and the variation of ranging from –0.03 to 0.03 at saturation density with isospin asymmetry , the has a stronger influence on the difference in between neutrons and protons, i.e., , than has. Meanwhile, at lower beam energies ( 0.25 GeV nucleon), is sensitive to both the and the . Moreover, the influence of on is more evident with the parameters of this study when using the soft, rather than stiff, symmetry energy.