高能重离子碰撞的最大能量密度估计和形成夸克物质的时空区域

Estimate of the Maximal Energy Density and Space-Time Region of the Quark Matter in High Energy Heavy Ion Collisions

本文修正了Bjorken的最大能量密度估计式,分析了碰撞核质量和入射能量对提高能量密度的影响。讨论了碰撞中心区,碎裂区的状态方程和流体动力学方程。指出在碎裂区很难实现夸克物质的原因是系统膨胀引起的能量扩散过快。预言了每对核子能量为100+100 GeV的^(197)Au-^(197)Au对撞在中心区实现相变的碰撞参数范围和时空区域。

The Bjorken formula about maximal energy density in heavy ion collisions is modified, the effective way to increase the energy density is also analysed. The hydrodynamic equations and the equations of state in central and fragmental regions are discussed. It is pointed out that because of the energy diffusion caused by expansion of the system, it is lifficult to produce quark matter in fragmental region. For Au-Au collisions on the RHIC to be buict at BNL, the space-time region where phase transition occur d and the corresponding extent of impact par- ameter are predicted.