论文标题
B-B,O-O,Ca-Ca和Au-Au碰撞中的冻结参数的调查39 GEV
Investigation of the freeze-out parameters in B-B, O-O, Ca-Ca and Au-Au collisions at 39 GeV
论文作者
论文摘要
我们分析了硼,氧气(B-B),氧氧(O-O)和钙 - 钙(CA-CA)中心碰撞中的质子,Deuteron和Triton的横向动量光谱,以及在39 Gold(AU-AU)碰撞中使用爆炸型模型的Gold-Gold(AU-AU)碰撞中的几种中心性bin中的钙 - 氧气(CA-CA)中心碰撞。通过动力学冷冻温度,横向流速和动力学冻结体积的大量特性是通过模型从最小平方方法中提取的。我们观察到,随着粒子的剩余质量的增加,动力学冷冻温度变得更大,而横向流速度和动力学冻结体积会减小。还发现这些参数取决于系统的大小。系统尺寸越大,它们越大。此外,外周Au-AU碰撞中的动力学冻结温度接近中央O-O碰撞。我们还观察到上述参数取决于中心性,并且它们从中央碰撞到周围碰撞。此外,我们还提取了熵索引参数$ q $,以及显示多重性的参数$ n_0 $。它们俩都取决于系统相互作用的大小,粒子的休息质量和中心性。 $ Q $和$ n_0 $对于较轻的颗粒都较大,并且对于大型系统而言,前者较小,而后者则更大,而前者的中心性会降低,而后者则增加。
We analyzed the transverse momentum spectra of proton, deuteron and triton in Boron-Boron (B-B), Oxygen-Oxygen (O-O), and Calcium-Calcium (Ca-Ca) central collisions, as well as in several centrality bins in Gold-Gold (Au-Au) collisions at 39 GeV by using the blast wave model with Tsallis statistics. The bulk properties in terms of kinetic freeze-out temperature, transverse flow velocity and kinetic freeze-out volume are extracted from the model by the least square method. We observed that with increasing the rest mass of the particle, the kinetic freeze-out temperature becomes larger, while transverse flow velocity and the kinetic freeze-out volume reduces. These parameters are also found to depend on the size of the system. Larger the size of the system, the larger they are. Furthermore, the kinetic freeze-out temperature in peripheral Au-Au collisions is close to the central O-O collisions. We also observed that the above parameters depend on the centrality, and they decrease from central to peripheral collisions. Besides, we also extracted the entropy-index parameter $q$, and the parameter $N_0$ which shows the multiplicity. Both of them depend on the size of interacting the system, rest mass of the particle and centrality. Both $q$ and $N_0$ are larger for lighter particles, and the former is smaller for large systems while the latter is larger, and the former decrease with increasing centrality while the latter increase.