Azimuthal anisotropy, especially for the multi-strange hadrons, is expected to be sensitive to the dynamical evolution in the early stage of high energy nuclear collisions. In this paper we present the latest results ...Azimuthal anisotropy, especially for the multi-strange hadrons, is expected to be sensitive to the dynamical evolution in the early stage of high energy nuclear collisions. In this paper we present the latest results of multi-strange hadron elliptic flow in Au ＋ Au collisions at √SNN=200GeV from the STAR experiment at RHIC. The number-of-quark scaling is evidenced with φ（ss） and Ω（sss） with highly statistical data, which shows strange quark collectivity at RHIC. The u2 of φ meson is found to be consistent with that of proton within statistical error bars at pw 〈 1 GeV/c.展开更多
The Ω and ? production in relativistic heavy-ion collisions is studied in a dynamical quark coalescence model using the phase space information of strange quarks from a multiphase transport(AMPT) model. Enhanced loca...The Ω and ? production in relativistic heavy-ion collisions is studied in a dynamical quark coalescence model using the phase space information of strange quarks from a multiphase transport(AMPT) model. Enhanced local parton density fluctuation is implemented in the AMPT to simulate the QCD phase transition dynamics. By studying the transverse momentum pT spectra and the elliptic flow of the multi-strangeness particles, such as Ω and ? , and the Ω/? ratio as a function of pTin the AMPT,we find that the new development improves the description of experimental data. The study motivates further experimental investigations of Ω and ? production in phase Ⅱ of the Beam Energy Scan program at RHIC.展开更多
Within the framework of a multiphase transport model, we study the production and properties of Ω andφ in Au ＋ Au collisions with a new set of parameters for （s（NN））^（1/2）= 200 GeV and with the original set o...Within the framework of a multiphase transport model, we study the production and properties of Ω andφ in Au ＋ Au collisions with a new set of parameters for （s（NN））^（1/2）= 200 GeV and with the original set of parameters for （s（NN））^（1/2）= 11.5 GeV. The AMPT model with string melting provides a reasonable description at （s（NN））^（1/2）= 200 GeV,while the default AMPT model describes the data well at （s（NN））^（1/2）= 11.5 GeV. This indicates that the system created at top RHIC energy is dominated by partonic interactions, while hadronic interactions become important at lower beam energy, such as （s（NN））^（1/2）= 11.5 GeV. The comparison of N（Ω^＋＋Ω^-）/[2N（φ）] ratio between data and calculations further supports the argument. Our calculations can generally describe the data of nuclear modification factor as well as elliptic flow.展开更多
We study the ground-state properties of the _(YY)^(6)He double hyperon for _(ΛΛ)^(6)He and _(ΩΩ)^(6)He nuclei in a threebody model(Y+Y+α).We solve two coupled Faddeev equations corresponding to the three-body con...We study the ground-state properties of the _(YY)^(6)He double hyperon for _(ΛΛ)^(6)He and _(ΩΩ)^(6)He nuclei in a threebody model(Y+Y+α).We solve two coupled Faddeev equations corresponding to the three-body configurations(αY,Y)and(YY,α)in configuration space with the hyperspherical harmonics expansion method by employing the most recent hyperon-hyperon interactions obtained from lattice QCD simulations.Our numerical analysis for _(ΛΛ)^(6)He,using threeΛΛlattice interaction models,leads to a ground state binding energy in the(-7.468,-7.804)MeV domain and the separations <r_(Λ-Λ)>and <r_(α-Λ)>in the domains of(3.555,3.629)fm and(2.867,2.902)fm,respectively.The binding energy of the double-Ω hypenucleus _(ΩΩ)^(6)He leads to -67.21 MeV and consequently to smaller separations <r_(Ω-Ω)>=1.521 fm and <r_(α-Ω)>=1.293 fm.In addition to geometrical properties,we study the structure of ground-state wave functions and show that the main contributions are from the s-wave channels.Our results are consistent with the existing theoretical and experimental data.展开更多
基金supported by National Natural Science Foundation of China (No. 10905029)by China Postdoctoral Science Foundation(No. 20100480017)by the U.S. Department of Energy under Contract No. DE-AC03-76SF00098
文摘Azimuthal anisotropy, especially for the multi-strange hadrons, is expected to be sensitive to the dynamical evolution in the early stage of high energy nuclear collisions. In this paper we present the latest results of multi-strange hadron elliptic flow in Au ＋ Au collisions at √SNN=200GeV from the STAR experiment at RHIC. The number-of-quark scaling is evidenced with φ（ss） and Ω（sss） with highly statistical data, which shows strange quark collectivity at RHIC. The u2 of φ meson is found to be consistent with that of proton within statistical error bars at pw 〈 1 GeV/c.
基金supported in part by the Major State Basic Research Development Program in China(Nos.2014CB845400 and2015CB856904)the National Natural Science Foundation of China(Nos.11775288,11421505,and 11520101004)
文摘The Ω and ? production in relativistic heavy-ion collisions is studied in a dynamical quark coalescence model using the phase space information of strange quarks from a multiphase transport(AMPT) model. Enhanced local parton density fluctuation is implemented in the AMPT to simulate the QCD phase transition dynamics. By studying the transverse momentum pT spectra and the elliptic flow of the multi-strangeness particles, such as Ω and ? , and the Ω/? ratio as a function of pTin the AMPT,we find that the new development improves the description of experimental data. The study motivates further experimental investigations of Ω and ? production in phase Ⅱ of the Beam Energy Scan program at RHIC.
基金Supported by National Natural Science Foundation of China(11421505,11520101004,11220101005,11275250,11322547)Major State Basic Research Development Program in China(2014CB845400,2015CB856904)Key Research Program of Frontier Sciences of CAS(QYZDJSSW-SLH002)
文摘Within the framework of a multiphase transport model, we study the production and properties of Ω andφ in Au ＋ Au collisions with a new set of parameters for （s（NN））^（1/2）= 200 GeV and with the original set of parameters for （s（NN））^（1/2）= 11.5 GeV. The AMPT model with string melting provides a reasonable description at （s（NN））^（1/2）= 200 GeV,while the default AMPT model describes the data well at （s（NN））^（1/2）= 11.5 GeV. This indicates that the system created at top RHIC energy is dominated by partonic interactions, while hadronic interactions become important at lower beam energy, such as （s（NN））^（1/2）= 11.5 GeV. The comparison of N（Ω^＋＋Ω^-）/[2N（φ）] ratio between data and calculations further supports the argument. Our calculations can generally describe the data of nuclear modification factor as well as elliptic flow.
基金Supported by the National Science Foundation under Grant No.NSF-PHY-2000029 with Central State University。
文摘We study the ground-state properties of the _(YY)^(6)He double hyperon for _(ΛΛ)^(6)He and _(ΩΩ)^(6)He nuclei in a threebody model(Y+Y+α).We solve two coupled Faddeev equations corresponding to the three-body configurations(αY,Y)and(YY,α)in configuration space with the hyperspherical harmonics expansion method by employing the most recent hyperon-hyperon interactions obtained from lattice QCD simulations.Our numerical analysis for _(ΛΛ)^(6)He,using threeΛΛlattice interaction models,leads to a ground state binding energy in the(-7.468,-7.804)MeV domain and the separations <r_(Λ-Λ)>and <r_(α-Λ)>in the domains of(3.555,3.629)fm and(2.867,2.902)fm,respectively.The binding energy of the double-Ω hypenucleus _(ΩΩ)^(6)He leads to -67.21 MeV and consequently to smaller separations <r_(Ω-Ω)>=1.521 fm and <r_(α-Ω)>=1.293 fm.In addition to geometrical properties,we study the structure of ground-state wave functions and show that the main contributions are from the s-wave channels.Our results are consistent with the existing theoretical and experimental data.
