Numerical Simulation of Quark-Gluon Systems with Massvely Parallel Computer QCDPAX

为了在1989年通过特别促进研究资助计划建立的大规模并行计算机QCDPAX上进行大规模的格子QCD计算，通过购买一台工作站，进一步配备了QCDPAX程序的开发环境。在此环境下，对有限温度下的胶子系统进行了高态TICS蒙特卡罗模拟。首先，将时间方向上的晶格尺寸固定为4，模拟了空间尺寸为12X12X24和24X24X36的两个晶格。当规范耦合常数近似为相变点时，分别进行了91万次和71万次迭代。然后，将时间晶格尺寸增加到6，分别模拟了空间尺寸为24X24X24和36X36X48的晶格分别有500,000和1,200,000个相互作用。在36X36X48X6晶格上的后一种模拟在很大程度上改进了先前的计算，无论是在晶格的大小上还是在迭代次数上。例如，通过这一模拟，我们可以得出结论，在小晶格上，当时间晶格尺寸为6时，与一阶解禁闭相变相关的潜热的值大约是先前估计的一半。其次，我们计算了24X24X24X54晶格上的强子质量。通过比以前的模拟更精确的计算，我们发现唯象质量公式在夸克质量为奇夸克质量的1/3的情况下适用得很好。在此基础上，我们研究了不同口味数的夸克的禁闭，发现即使在无限大的规范耦合常数下，当口味数大于7时，禁闭也会消失。

In order to perform a large scale computation of lattice QCD with the massively parallel computer QCDPAX, which is constructed through the Grant-in-Aid for Specially Promoted Research in 1989, the environment for the development of QCDPAX-programs is further equipped by purchasing a workstation. On this environment, a high states tics Monte Carlo simulation of the gluon system at finite temperature is performed. First, fixing the lattice size in the temporal direction to be 4, two lattices with the spatial size of 12X12X24 and 24X24X36 are simulated. With the gauge coupling constant approximately at the phase transition point, 910, 000 and 710, 000 iterations are performed respectively. Then, increasing the temporal lattice size up to 6, lattices with the spatial size of 24X24X24 and 36X36X48 are simulated with 500, 000 and 1, 200, 000 interactions respectively. The latter simulation on the 36X36X48X6 lattice improves the previous computations to a large extent both in the size of the lattice and in the number of iterations. With this simulation, we can, for example, conclude that the value of the latent heat associated with the first order deconfining phase transition is about one half of a previous estimation on a small lattice for the case of the temporal lattice size 6. Secondly, we calculated the mass of hadrons on a 24X24X24X54 lattice. With a computation with higher precision than previous simulations, we find that the phenomenological mass formula works well for the quark mass down to about 1/3 of the strange quark mass. Thidly, we studied the confinement of quarks with varying the number of flavors and find that the confinement is lost for the flavor number larger than 7 even with the infinitely large gauge coupling constant.