Determination of Orientations in Deformed U--U Collisions at 0.52GeV/u
WU Ke-Jun1,3, XIE Fei1, ZHOU You1, LIU Feng1,3, XU Nu 1,2
1Institute of Particle Physics, Huazhong Normal University, Wuhan 4300792 Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA3 Key Laboratory of Quark and Lepton Physics (Ministry of Education), Huzhong Normal University, Wuhan 430079
Determination of Orientations in Deformed U--U Collisions at 0.52GeV/u
WU Ke-Jun1,3, XIE Fei1, ZHOU You1, LIU Feng1,3, XU Nu 1,2
1Institute of Particle Physics, Huazhong Normal University, Wuhan 4300792 Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA3 Key Laboratory of Quark and Lepton Physics (Ministry of Education), Huzhong Normal University, Wuhan 430079
摘要The ART model is applied to study the deformed UU collision at HIRFL-CSR energy area corresponding to the high baryon density region in the QCD phase diagram. The time evolution of central baryon (energy) densities in central collisions at Eb =0.52GeV/u shows that different orientation collisions will lead to different lifetimes of high density, especially tip--tip UU collisions which have an extend lifetime for the high density phase by almost a factor of 2 compared to the body--body orientation collisions. In order to pick out the interesting tip--tip like events from a mass of random orientation collisions, we study the relation between stopping power R and impact parameter b in different orientation collisions and find that it can enhance the purity of tip--tip like events when R increases. Therefore, the high density and long lifetime events can be effectively distinguished by R selection.
Abstract：The ART model is applied to study the deformed UU collision at HIRFL-CSR energy area corresponding to the high baryon density region in the QCD phase diagram. The time evolution of central baryon (energy) densities in central collisions at Eb =0.52GeV/u shows that different orientation collisions will lead to different lifetimes of high density, especially tip--tip UU collisions which have an extend lifetime for the high density phase by almost a factor of 2 compared to the body--body orientation collisions. In order to pick out the interesting tip--tip like events from a mass of random orientation collisions, we study the relation between stopping power R and impact parameter b in different orientation collisions and find that it can enhance the purity of tip--tip like events when R increases. Therefore, the high density and long lifetime events can be effectively distinguished by R selection.
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