1.0 A GeV La+La碰撞中末态粒子分布的非对称性

The Anisotropic Distribution of Final State Particles in 1.0 A GeV La+La Collisions

对ＢｅｖａｌａｃＥＯＳ时间投影室１．０ＡＧｅＶＬａ＋Ｌａ碰撞实验，根据以流方向为ｚ轴的质心坐标系中末态粒子方位角分布的非对称性为极小的条件，确定了事件中４种质量范围（Ａ＝１、２、３、４）末态粒子的集合侧向流流角。在以流方向为ｚ轴的质心坐标系中研究了不同质量末态粒子极角分布，结果表明质量越大的粒子在流方向分布得越集中，侧向流的“流”值越大。

The flow angles for the final state particles with four kinds of mass number ( A =1、2、3、4) are determined for 1.0 A GeV La+La collisions in the Bevalac EOS time projection chamber by minimizing the azimuthal anisotropy in the center-of-mass coordinates systems where the z axis is rotated to various polar angles in the reaction plane. The study of the polar angle distribution for the final state particles with different mass in the systems with the z axis rotated to the flow angles indicates that the degree of concentration around the flow direction and the flow value increase with increasing mass number of the particles.