We studied experimental background reconstruction methods for the measurement of the D-D correlation using PYTHIA simulation.The like-sign(LS)and side-band(SB)background methods,which are widely used in the experiment...We studied experimental background reconstruction methods for the measurement of the D-D correlation using PYTHIA simulation.The like-sign(LS)and side-band(SB)background methods,which are widely used in the experimental measurements of single D-meson production yields,were deployed for correlation study.It was found that the LS method,which describes the combinatorial background of single D^(0) meson yields,fails to reproduce the correlated background in the D^(0)-D^(0) correlation measurement,while the SB background method yields a good description of the background for both single D^(0) yields and the correlated background of the D^(0)-D^(0) correlation measurement.We further examined the validity of the correlation methods under different signal-to-background ratios,providing direct references for experimental measurements.展开更多
Two-particle （two-fragment） azimuthal correlation functions are studied by using a simple formula which describes uniformly azimuthal distributions of final-state charged particles and nuclear fragments. This formul...Two-particle （two-fragment） azimuthal correlation functions are studied by using a simple formula which describes uniformly azimuthal distributions of final-state charged particles and nuclear fragments. This formula is obtained in the framework of a multi-source thermal model （or multi-source ideal gas model）. The calculated results are compared and found to be in agreement with the experimental data of charged hadrons and nuclear fragments in nucleus-nucleus collisions at intermediate and high energies.展开更多
A method for investigating the azimuthal correlations between directed and elliptic flow in heavy ion collisions is described. The transverse anisotropy of particle emission at AGS energies is investigated within the ...A method for investigating the azimuthal correlations between directed and elliptic flow in heavy ion collisions is described. The transverse anisotropy of particle emission at AGS energies is investigated within the RQMD model. It is found that the azimuthal correlations between directed and elliptic flow are sensitive to the incident energy and impact parameter. The fluctuations in the initial stage and dynamical evolution of heavy ion collisions are not negligible.展开更多
Multiparticle azimuthal correlations in central nucleus-nucleus collisions at high energy are described by a simple formula. The calculated results are in agreement with the experimental data of carbon and oxygen indu...Multiparticle azimuthal correlations in central nucleus-nucleus collisions at high energy are described by a simple formula. The calculated results are in agreement with the experimental data of carbon and oxygen induced interactions at Dubna energy. The comparison between the calculated results and experimental data shows that particles are emitted isotropically in the rest frame of the emission sources, and the emission sources have movements in momentum space.展开更多
Neighboring azimuthal bin-bin multiplicity correlation is suggested to be a good measure for internal layer-to-layer interactions of the formed matter in relativistic heavy ion collisions. It is shown to be directly r...Neighboring azimuthal bin-bin multiplicity correlation is suggested to be a good measure for internal layer-to-layer interactions of the formed matter in relativistic heavy ion collisions. It is shown to be directly related to the shear viscosity of the formed matter. As an application of this method, the shear viscosity in the samples generated by a multi-phase transport model （AMPT） is estimated. The results are in qualitative agreement with the theoretical calculation from microscopic interactions, i.e., the larger the scattering cross section, the smaller the shear viscosity.展开更多
基金supported in part by the National Natural Science Foundation of China(Nos.11890710,11890714,11905034)the Strategic Priority Research Program of Chinese Academy of Sciences(No.XDB34000000)。
文摘We studied experimental background reconstruction methods for the measurement of the D-D correlation using PYTHIA simulation.The like-sign(LS)and side-band(SB)background methods,which are widely used in the experimental measurements of single D-meson production yields,were deployed for correlation study.It was found that the LS method,which describes the combinatorial background of single D^(0) meson yields,fails to reproduce the correlated background in the D^(0)-D^(0) correlation measurement,while the SB background method yields a good description of the background for both single D^(0) yields and the correlated background of the D^(0)-D^(0) correlation measurement.We further examined the validity of the correlation methods under different signal-to-background ratios,providing direct references for experimental measurements.
基金Supported by National Natural Science Foundation of China(10975095,11075100)the Natural Science Foundation of Shanxi Province(2007011005,2011011001-2)the Developing Project of Science and Technology of Shanxi Province(20091016)
文摘Two-particle （two-fragment） azimuthal correlation functions are studied by using a simple formula which describes uniformly azimuthal distributions of final-state charged particles and nuclear fragments. This formula is obtained in the framework of a multi-source thermal model （or multi-source ideal gas model）. The calculated results are compared and found to be in agreement with the experimental data of charged hadrons and nuclear fragments in nucleus-nucleus collisions at intermediate and high energies.
基金Supported by Natural Science Foundation of Heilongjiang Province (A0208)Science Foundation of Harbin Institute of Technology (HIT.2002.47, HIT.2003.33)
文摘A method for investigating the azimuthal correlations between directed and elliptic flow in heavy ion collisions is described. The transverse anisotropy of particle emission at AGS energies is investigated within the RQMD model. It is found that the azimuthal correlations between directed and elliptic flow are sensitive to the incident energy and impact parameter. The fluctuations in the initial stage and dynamical evolution of heavy ion collisions are not negligible.
基金Supported by National Natural Science Foundation of China (10975095) Natural Science Foundation of Shanxi Province(2007011005)
文摘Multiparticle azimuthal correlations in central nucleus-nucleus collisions at high energy are described by a simple formula. The calculated results are in agreement with the experimental data of carbon and oxygen induced interactions at Dubna energy. The comparison between the calculated results and experimental data shows that particles are emitted isotropically in the rest frame of the emission sources, and the emission sources have movements in momentum space.
基金Supported by NSFC(10835005,11221504)MOE of China(IRT0624,B08033)Fundamental Research Funds for Central Universities(CUGL 100237)
文摘Neighboring azimuthal bin-bin multiplicity correlation is suggested to be a good measure for internal layer-to-layer interactions of the formed matter in relativistic heavy ion collisions. It is shown to be directly related to the shear viscosity of the formed matter. As an application of this method, the shear viscosity in the samples generated by a multi-phase transport model （AMPT） is estimated. The results are in qualitative agreement with the theoretical calculation from microscopic interactions, i.e., the larger the scattering cross section, the smaller the shear viscosity.
