强子内部激发和QCD真空在核热力学行为上的效应

对于非常高的温度,基于一个混合相模型,研究了强子的内部激发和QCD真空在核子系统的热力学行为上的效应。结果表明这两个效应带来了一个合理的相变图象,它重大地改变了系统的热力学行为。

相对论性流体力学方程组的数值解法

本文叙述了用有限差分方法求解相对论性流体力学方程组的数值解的方法,给出了差分格式推导的详细步骤及处理含有相变问题的求解方法,并给出了若干具体问题的解的图象。

信息技术与学科教学的有机结合初探

信息技术与学科有机结合是时代的需要,是传统的课堂教学模式与现代的教育教学课堂模式的转变需要,是向45分钟要质量、效益的关键所在。通过探讨后,对当前的课堂教育教学具有一定的借鉴和指导作用。

Hard Photons from a Non-Equilibrated Quark-Gluon Plasma with Finite Baryon Density at a Two-Loop Level

We study hard photon production from a two-loop level （bremsstrahlung and annihilation with scattering） in a chemically equilibrating quark-gluon plasma at finite baryon density based on Jüttner distribution of partons of the system. We find that the photon yield from the two-loop level increases obviously with the increasing initial quark chemical potential.

Photons from Quark and Hadron Phases in Au ＋ Au Collisions

Based on a relativistic hydrodynamic model describing the evolution of the chemically equilibrating quark-gluon plasma system with finite baryon density in a 3＋1-dimensional spacetime, we compute photons from the quark phase, hadronic phase and initial non-thermal contributions. It is found that due to the effects of the initial quark chemical potential, chemical equilibration and rapid expansion of the system, the photon yield of the quark-gluon plasma is strongly suppressed, and photons from hadronic matter and initial non-thermal contributions almost reproduce experimental data.

Photon Production in a Chemically Equilibrating Quark-Gluon Plasma at Finite Baryon Density： Complete Leading Order Results

We investigate hard photon production of the near-collinear bremsstrahlung and a new process called the inelastic pair annihilation, fully including the LPM effect, in a chemically equilibrating quark-gluon plasma at finite baryon density, and find that the effect of the system evolution on the photon production and large contribution of the bremsstrahlung make the total photon yield of the two processes as a strongly increasing function of the initial quark chemical potential.

Intermediate Mass Dilepton Production in an Expanding Baryon-rich Quark--Gluon Matter

The intermediate mass dileptons from the quark phase,secondary hadronic processes and background sources have been studied based on a relativistic hydrodynamic model.Due to the effect of the phase boundary on the evolution of the system the contribution from the quark phase is much more important than that from secondary processes and is even comparable with that from background sources.This leads to a spectrum without the obvious humps of the hadronic phase contribution and the yield increasing with the incident energy of colliding nuclei.It is shown that the enhancement of dileptons is a signature for the formation of the quark--gluon plasma.

Intermediate Mass Dilepton Production in a Chemically Equilibrating Quark-Gluon Matter

Dilepton production during the chemical equilibration of quark-gluon matter with a finite baryon density has been studied. We find that due to the slowing down of the cooling rate and the high initial temperature of the quark-gluon matter produced at RHIC energies, the quark phase contribution to dileptons with intermediate masses is significantly heightened and is much larger than that calculated by the evolution of the thermodynamic equilibrium system. The latter has shown an enhancement of intermediate mass dileptons from the quark phase. Therefore, such an enhancement of dileptons should be a signature for quark-gluon matter formation.

Dilepton Production in an Expanding Hot Baryon-Rich Quark-Gluon Matter

Under thermodynamic equilibrium, the initial values of the quark-gluon system from relativistic nucleus-nucleus collisions are obtained. From these initial values we have studied the dilepton production on the basis of the relativistic hydrodynamic model, and found that with increasing incident energy a characteristic plateau indicating the formation of the quark-gluon plasma appears in the total yield.

Dilepton Production in an Expanding Hot Baryon-Rich Quark-Gluon Matter

From the full stopping scenario,a relativistic hydrodynamic model describing the evolution of the baryon-rich quark-gluon matter fire-cylinder has been established.Based on it,the rapidity Distribution of dileptons with intermediate invariant masses has been studied.It is found that the quark phase gives the dominant contribution to the dilepton spectrum due to the influence of the phase boundary on the evolution of the system,especially the dilepton yield is strongly suppressed with the increasing rapidity.

Dependence of Dilepton Production in the Baryon-Rich Quark-Gluon Fireball on the Initial Temperature

In the study of dilepton production of a baryon-rich quark-gluon fireball based on the full stopping scenario via a relativistic hydrodynamic model,it is found that for the fixed initial baryon chemical potential with increasing initial temperature a peak indicating the formation of the baryon-rich quark-gluon matter appears in the total dilepton yield.

Dilepton Distribution as a Signature for the Baryon-Rich Quark-Gluon Matter

From the full stopping scenario,the dilepton production in the baryon-rich quark-gluon fireball based on a relativistic hydrodynamic model is studied,and it is found that with increasing incident energy a characteristic plateau indicating the formation of the baryon-rich quark-gluon matter appears in the total yield.

Dileptons from a Chemically Equilibrating Quark-Gluon Plasma at Finite Baryon Density

We perform a complete calculation for the dilepton production from the processes qq→ll Compton-like （qg-＋qll, qg→qU, qq→gll, gluon fusion gg→cc, annihilation qq→cc as well as multiple scattering of quarks in a chemically equilibrating quark-gluon plasma system at finite baryon density. It is found that quark-antiquark annihilation, Compton-like, gluon fusion and multiple scattering of quarks give important contribution. Moreover, the increase of the quark phase life-time with increasing initial quark chemical potential makes the dilepton yield as an increasing function of the initial quark chemical potential.

化学非平衡夸克-胶子物质中等质量双轻子的产生

研究了正在进行化学平衡的富重子夸克 胶子物质的双轻子产生 ,发现由于产生在RHIC能量的化学非平衡的富重子夸克 胶子物质冷却慢和高的初始温度 ,导致中等质量双轻子产生重大增强 .因此 ,中等质量双轻子的增强可以是夸克 胶子物质形成的信号 .同时 ,这个增强能补偿由于初始夸克化学势增加引起的双轻子抑制 ,因而双轻子产额的抑制不再是夸克 胶子物质产生的信号 .