关键词: 
铅-铅碰撞 /
带电粒子 /
方位角分布 /
多源热模型

摘要: 利用多源热模型分析了ATLAS实验组2.76 TeV 铅-铅碰撞中产生的、带电粒子在多个不同中心度事例中的方位角分布，并与n=2,4,6 和n=2 的傅里叶级数形式的方位角分布进行了比较。同时，利用由多源热模型得到的散射源在横动量空间的结构参数，计算了散射源在横动量空间的各向异性率和相对膨胀率，且与
相关傅里叶系数进行了比较。在各个中心度区间，横动量空间的各向异性率和相对膨胀率都小于相应的傅里叶系数，椭圆各向异性是末态方位角分布中最主要的成分，其他成分的各向异性在各中心度区间的贡献不同且作用不可忽视。

We analyze the azimuthal distributions of charged particles produced in 2.76 TeV Pb-Pb collisionsfrom ATLAS experimental group in eight different centralities by using the multi-source thermal model. Themodeling results are compared with the results from Fourier series forms with n = 2,4,6 and n = 2. Meanwhile,the anisotropy ratios and the relative expansion rates of scattering source in transverse momentum space are  calculated applying the transverse structural parameters of multi-source thermal model, and the modeling results are compared with the associated fourier coefficients. The anisotropy ratios and the relative expansion rates are less than the corresponding fourier coefficients in transverse momentum space in different center intervals. Elliptical anisotropy is main component in azimuthal distribution. Other anisotropies have different contributions in different centralities, and these contributions cannot be neglected.