The space-time characters of the pion-emitting sources produced in the heavy ion collisions at the Large Hadron Collider （LHC） energies are investigated in a granular source model of quark-gluon plasma droplets. The...The space-time characters of the pion-emitting sources produced in the heavy ion collisions at the Large Hadron Collider （LHC） energies are investigated in a granular source model of quark-gluon plasma droplets. The results of two-pion interferometry indicate that the longi- tudinal interferometry radius is sensitive to the initial breakup time of the system. For a larger breakup time the values of the longitudinal interferometry radius for the LHC source are larger than that of the source produced in the collisions at the Relativistic Heavy Ion Collider＇s （RHIC） top energy. However, the values of the longitudinal radius are smaller if the source fragments at a smaller breakup time with a higher initial temperature of the droplets. The values of the transverse interferometry radius in the ＂side＂ direction for the LHC sources are larger than those for the RHIC source. The imaging analyses for the characteristic quantities of the granular sources are consistent with the interferometry radii.展开更多
We examine the two-pion Hanbury-Brown-Twiss （HBT） interferometry for the particle-emitting source produced in heavy ion collisions at HIRFL-CSR energy. The source evolution is described by relativistic hydrodynamics...We examine the two-pion Hanbury-Brown-Twiss （HBT） interferometry for the particle-emitting source produced in heavy ion collisions at HIRFL-CSR energy. The source evolution is described by relativistic hydrodynamics with three kinds of equations of state for chemical equilibrium （CE）, chemical freeze-out （CFO）, and partial chemical equilibrium （PCE） models, respectively. We investigate the effects of particle decay, multiple scattering, and source collective expansion on the two-pion interferometry results. We find that the HBT radii of the evolution source for the CFO and PCE The HBT lifetime for the CFO model is smaller than those models are smaller than that for the CE model. for the PCE and CE models. The particle decay increases the HBT radius and lifetime while the source expansion decreases the HBT radius. The multiple scattering effect on the HBT results can be neglected based on our model calculations.展开更多
We examine two-pion Bose-Einstein correlations for partially coherent particle-emitting sources within quantum statistical formal- ism, where the sources are treated as classical currents with chaotic and coherent com...We examine two-pion Bose-Einstein correlations for partially coherent particle-emitting sources within quantum statistical formal- ism, where the sources are treated as classical currents with chaotic and coherent components. The two-pion correlation functions of the partially coherent sources contain a phase which is sensitive to the asymmetry of the source emission function. We investigate the influence of source opacity and expansion in high energy heavy ion collisions on the phase by Monte Carlo calculations. We find that these two physical effects shift the phase from zero. The Gaussian-formula fit results to the simulated two-pion correlation functions indicate that the opaque and expansion effects lead to a smaller interferometry radius Rout and a larger 2 parameter.展开更多
We examine the space-time structure of particle-emitting source and two-pion interferometry in a smoothed hydrodynamic model with fluctuating initial conditions. An equation of state with a crossover transition betwee...We examine the space-time structure of particle-emitting source and two-pion interferometry in a smoothed hydrodynamic model with fluctuating initial conditions. An equation of state with a crossover transition between quark-gluon plasma and hadronic gas is adopted in the description of the system evolution. We find that the fluctuating initial conditions lead to inhomogeneous particle-emitting sources. The interferometry results of Rs and Ro indicate that both the source size and the duration of pion emission decrease when the freeze-out temperature increases. The values of Ro/Rs obtained by our simulated two-pion interferometry are consistent with the previous results of smoothed particle hydrodynamics, and smaller than those calculated in usual hydrodynamic models.展开更多
The space-time evolution of the （1＋1）-dimensional viscous hydrodynamics with an initial quarkgluon plasma （QGP） produced in ultrarelativistic heavy ion collisions is studied numerically. The particleemitting sour...The space-time evolution of the （1＋1）-dimensional viscous hydrodynamics with an initial quarkgluon plasma （QGP） produced in ultrarelativistic heavy ion collisions is studied numerically. The particleemitting sources undergo a crossover transition from the QGP to hadronic gas. We take into account a usual shear viscosity for the strongly coupled QGP as well as the bulk viscosity which increases significantly in the crossover region. The two-pion Hanbury-Brown-Twiss （HBT） interferometry for the viscous hydrodynamic sources is performed. The HBT analyses indicate that the viscosity effect on the two-pion HBT results is small if only the shear viscosity is taken into consideration in the calculations. The bulk viscosity leads to a larger transverse freeze-out configuration of the pion-emitting sources, and thus increases the transverse HBT radii. The results of the longitudinal HBT radius for the source with Bjorken longitudinal scaling are consistent with the experimental data.展开更多
We investigate the single-event two-pion correlation functions for the hydrodynamic particle-emitting sources with the fluctuating initial conditions generated by the Heavy Ion Jet Interaction Generator （HIJING）. Us...We investigate the single-event two-pion correlation functions for the hydrodynamic particle-emitting sources with the fluctuating initial conditions generated by the Heavy Ion Jet Interaction Generator （HIJING）. Using a three-dimension fast Fourier transform （FFT）, we further extract the source functions from the single-event correlation functions. It is found that the inhomogeneity of the hydrodynamic sources with the fluctuating initial conditions lead to event-by-event fluctuations of the correlation functions and source functions.展开更多
基金supported by National Natural Science Foundation of China (Nos. 10775024, 11075027)
文摘The space-time characters of the pion-emitting sources produced in the heavy ion collisions at the Large Hadron Collider （LHC） energies are investigated in a granular source model of quark-gluon plasma droplets. The results of two-pion interferometry indicate that the longi- tudinal interferometry radius is sensitive to the initial breakup time of the system. For a larger breakup time the values of the longitudinal interferometry radius for the LHC source are larger than that of the source produced in the collisions at the Relativistic Heavy Ion Collider＇s （RHIC） top energy. However, the values of the longitudinal radius are smaller if the source fragments at a smaller breakup time with a higher initial temperature of the droplets. The values of the transverse interferometry radius in the ＂side＂ direction for the LHC sources are larger than those for the RHIC source. The imaging analyses for the characteristic quantities of the granular sources are consistent with the interferometry radii.
基金Supported by National Natural Science Foundation of China (10575024,10775024)
文摘We examine the two-pion Hanbury-Brown-Twiss （HBT） interferometry for the particle-emitting source produced in heavy ion collisions at HIRFL-CSR energy. The source evolution is described by relativistic hydrodynamics with three kinds of equations of state for chemical equilibrium （CE）, chemical freeze-out （CFO）, and partial chemical equilibrium （PCE） models, respectively. We investigate the effects of particle decay, multiple scattering, and source collective expansion on the two-pion interferometry results. We find that the HBT radii of the evolution source for the CFO and PCE The HBT lifetime for the CFO model is smaller than those models are smaller than that for the CE model. for the PCE and CE models. The particle decay increases the HBT radius and lifetime while the source expansion decreases the HBT radius. The multiple scattering effect on the HBT results can be neglected based on our model calculations.
基金supported by the Natural Science Foundation of Heilongjiang Province of China (Grant No. A201005)
文摘We examine two-pion Bose-Einstein correlations for partially coherent particle-emitting sources within quantum statistical formal- ism, where the sources are treated as classical currents with chaotic and coherent components. The two-pion correlation functions of the partially coherent sources contain a phase which is sensitive to the asymmetry of the source emission function. We investigate the influence of source opacity and expansion in high energy heavy ion collisions on the phase by Monte Carlo calculations. We find that these two physical effects shift the phase from zero. The Gaussian-formula fit results to the simulated two-pion correlation functions indicate that the opaque and expansion effects lead to a smaller interferometry radius Rout and a larger 2 parameter.
基金Supported by National Natural Science Foundation of China (10775024)Foundation of Theoretical Nuclear Physics Center of National Laboratory of Heavy Ion Accelerator of Lanzhou
文摘We examine the space-time structure of particle-emitting source and two-pion interferometry in a smoothed hydrodynamic model with fluctuating initial conditions. An equation of state with a crossover transition between quark-gluon plasma and hadronic gas is adopted in the description of the system evolution. We find that the fluctuating initial conditions lead to inhomogeneous particle-emitting sources. The interferometry results of Rs and Ro indicate that both the source size and the duration of pion emission decrease when the freeze-out temperature increases. The values of Ro/Rs obtained by our simulated two-pion interferometry are consistent with the previous results of smoothed particle hydrodynamics, and smaller than those calculated in usual hydrodynamic models.
基金Supported by National Natural Science Foundation of China (11075027)
文摘The space-time evolution of the （1＋1）-dimensional viscous hydrodynamics with an initial quarkgluon plasma （QGP） produced in ultrarelativistic heavy ion collisions is studied numerically. The particleemitting sources undergo a crossover transition from the QGP to hadronic gas. We take into account a usual shear viscosity for the strongly coupled QGP as well as the bulk viscosity which increases significantly in the crossover region. The two-pion Hanbury-Brown-Twiss （HBT） interferometry for the viscous hydrodynamic sources is performed. The HBT analyses indicate that the viscosity effect on the two-pion HBT results is small if only the shear viscosity is taken into consideration in the calculations. The bulk viscosity leads to a larger transverse freeze-out configuration of the pion-emitting sources, and thus increases the transverse HBT radii. The results of the longitudinal HBT radius for the source with Bjorken longitudinal scaling are consistent with the experimental data.
基金Supported by National Natural Science Foundation of China(11075027,11275037)
文摘We investigate the single-event two-pion correlation functions for the hydrodynamic particle-emitting sources with the fluctuating initial conditions generated by the Heavy Ion Jet Interaction Generator （HIJING）. Using a three-dimension fast Fourier transform （FFT）, we further extract the source functions from the single-event correlation functions. It is found that the inhomogeneity of the hydrodynamic sources with the fluctuating initial conditions lead to event-by-event fluctuations of the correlation functions and source functions.
