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Thermodynamic properties at the kinetic freeze-out in the Au + Au and Cu + Cu collisions at the RHIC using the Tsallis distribution

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Nuclear Science and Techniques 2023年第10期34卷 73-82页

作者： Wei-Hao Wu Jun-Qi Tao Hua Zheng Wen-Chao Zhang Xing-Quan Liu Li-Lin Zhu Aldo Bonasera School of Physics and Information Technology Shaanxi Normal UniversityXi’an 710119China Key Laboratory of Quark and Lepton Physics(MOE)and Institute of Particle Physics Central China Normal UniversityWuhan 430079China Institute of Nuclear Science and Technology Sichuan UniversityChengdu 610064China Department of Physics Sichuan UniversityChengdu 610064China Cyclotron Institute Texas A&M UniversityCollege StationTX 77843USA Laboratori Nazionali del Sud INFN95123 CataniaItaly

The thermodynamic properties of charged particles,such as the energy density,pressure,entropy density,particle density,and squared speed of sound at the kinetic freeze-out in the Au+Au collisions from the relativistic heavy ion collider (RHIC)beam energy scan program √S_(NN) and in the Cu+Cu collisions at √S_(NN),200 GeV are studied using the thermodynamically consistent Tsallis *** energy density,pressure,and particle density decrease monotonically with the collision energy for the same collision centrality;These properties also decrease monotonically from the central to peripheral collisions at the same collision *** the scaled energy densityε∕T^(4) and scaled entropy density s∕T^(3) demonstrate the opposite trend with the collision energy for the same collision *** is a correlation betweenε∕T^(4) and s∕T^(3) at the same *** addition,the squared speed of sound was calculated to determine that all the collision energies share nearly the same value at different collision centralities.

关键词： Heavy-ion collision Tsallis distribution Kinetic freeze-out Energy density entropy density Particle density Squared speed of sound Pressure

The generalized Stefan-Boltzmann law of a rectilinear non-uniformly accelerating Kinnersley black hole

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Chinese Physics B 2009年第2期18卷 457-461页

作者：蒋继建孟庆苗王帅 Department of Physics Heze University

Using entropy density of Dirac field near the event horizon of a rectilinear non-uniformly accelerating Kinnersley black hole, the law for the thermal radiation of black hole is studied and the instantaneous radiation energy density is obtained. It is found that the instantaneous radiation energy density of a black hole is always proportional to the quartic of the temperature on event horizon in the same direction. That is to say, the thermal radiation of a black hole always satisfies the generalized Stefan-Boltzmann law. In addition, the derived generalized Stefan Boltzmann coefficient is no longer a constant, but a dynamic coefficient related to the space-time metric near the event horizon and the changing rate of the event horizon in black holes.

关键词： Kinnersley black hole entropy density thin film model instantaneous radiation energy density

The thermal radiation from dynamic black holes

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Science China(Physics,Mechanics & Astronomy) 2008年第7期51卷 923-930页

作者： MENG QingMiao JIANG JiJian Department of Physics Heze UniversityHeze 274015China

Using the related formula of dynamic black holes, the instantaneous radiation energy density of the general spherically symmetric charged dynamic black hole and the arbitrarily accelerating charged dynamic black hole is calculated. It is found that the instantaneous radiation energy density of black hole is always proportional to the quartic of the temperature of event horizon in the same direction. The proportional coefficient of generalized Stefan-Boltzmann is no longer a constant, and it becomes a dynamic coefficient that is related to the event horizon changing rate, space-time structure near event horizon and the radiation absorption coefficient of the black hole. It is shown that there should be an internal relation between the gravitational field around black hole and its thermal radiation.

关键词： entropy density thin film model instantaneous radiation energy density generalized Stefan-Boltzmann coefficient event horizon

Shear and bulk viscosity of high-temperature gluon plasma

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Chinese Physics C 2018年第6期42卷 59-66页

作者： Le Zhang De-Fu Hou Institute of Particle Physics and Key Laboratory of Quark and Lepton Physics(MOE) Central China Normal UniversityWuhan 430079China The College of Post and Telecommunication Wuhan Institute of TechnologyWuhan 430070China

We calculate the shear viscosity（η） and bulk viscosity（ζ） to entropy density（s） ratios η/s and ζ/s of a gluon plasma system in kinetic theory, including both the elastic gg←→gg forward scattering and the inelastic soft gluon bremsstrahlung gg←→ggg processes. Due to the suppressed contribution to η and ζ in the gg←→gg forward scattering and the effective g←→gg gluon splitting, Arnold, Moore and Yaffe（AMY） and Arnold, Dogan and Moore（ADM） have got the leading order computations for η and ζ in high-temperature QCD matter. In this paper, we calculate the correction to η and ζ in the soft gluon bremsstrahlung gg←→ggg process with an analytic *** find that the contribution of the collision term from the gg←→ggg soft gluon bremsstrahlung process is just a small perturbation to the gg←→gg scattering process and that the correction is at～ 5% level. Then, we obtain the bulk viscosity of the gluon plasma for the number-changing process. Furthermore, our leading-order result for bulk viscosity is the formula ζ∝（αs^2 T^3）/（lnαs^-1） in high-temperature gluon plasma.

关键词： shear viscosity bulk viscosity entropy density high-temperature gluon plasma soft gluon bremsstrahlung