600A MeV Au+Au碰撞的挤压效应分析

对600A MeV Au+Au碰撞实验的挤压效应进行了研究.在方位角分布分析的基础上,完成了对挤压效应的定量测量,有效地消除了估计反应平面离散对测量结果的影响.     

Effects of multi-collisions and surface on elliptic flow

The non-central Au+Au collision at center-of-mass energy √s_NN=200 GeV is simulated using AMPT model. It is found that both the integral and differential elliptic flow behaves differently for partons freezing out at different stages. It is shown that the integral elliptic flow of freeze-out partons decreases with time at the early stage, but increases with time at the late stage. The curve of transverse momentum distribution of elliptic flow of partons is more flatter at the early stage than at the late stage. The effect of surface emitting on elliptic flow is argued to be not neglectable.     

A Non-Zero Hadronic Elliptic Flow with a Vanished Partonic Elliptic Flow in a Coalescence Scenario

The elliptic flow of a hadron is calculated using a quark coalescence model based on the quark phase space distribution produced by a free streaming locally thermalized quark in a two-dimensional transverse plane at initial time. Without assuming the quark＇s elliptic flow, it is shown that the hadron obtains a non-zero elliptic flow in this model. The elliptic flow of the hadron is shown to be sensitive to both space momentum correlation and the hadron＇s internal structure. Quark number scaling is obtained only for some special cases.     

Size of the freeze-out source in high energy heavy ion collisions

Based on a hydro-inspired azimuthally symmetric emission function, we analyze the HBT radius R_s and the single-particle transverse momentum spectra in Au+Au collisions measured by the STAR Collaboration at √s_NN=200 GeV. The results show that consistent assumptions about transverse density (and/or flow profile) in the calculation of the HBT radius R_s and single-particle spectral analyses play an important role for understanding the size of the freeze-out source.     

Single-particle space-momentum angle distribution effect on two-pion HBT correlation in high-energy heavy-ion collisions

We analyze the transverse momentum dependence of HBT radii in relativistic heavy-ion collisions using several source models.Results indicate that the single-particle space-momentum angle distribution plays an important role in the transverse momentum dependence of HBT radii.In a cylinder source,we use several formulas to describe the transverse momentum dependence of HBT radii and the single-particle space-momentum angle distribution.We also make a numerical connection between them in the transverse plane.     

大学物理教学内容的模块化处理及教学设计

在理工科高等学校中, 大学物理课程是各专业学生的一门通识性必修基础课程, 在大学基础课程中占 有重要地位. 该课程在承担知识传授任务的同时, 还应该担负培养学生分析、 解决问题的能力及探索、 创新意识等方 面的功能. 为了更好地实现这一教学目标, 我们将大学物理核心内容划分为4个模块, 并对每一模块提出了具体的 教学方案     

大功率半导体激光器远场光分布特性

对于以TM模工作的大功率半导体激光器,基于偏轴高斯光束模型,推导了描述其光波传播特性的非傍轴矢量场模型,数值计算了大功率半导体激光器光束的远场光强分布和发散角特性,讨论了bar型半导体激光器的远场光分布特性,给出了bar型半导体激光器的远场光强分布模型及数值仿真结果.仿真结果表明,大功率半导体激光器的矢量光场和标量光场...     

Two-pion interferometry in heavy ion collisions at HIRFL-CSR energy

We examine the two-pion Hanbury-Brown-Twiss (HBT) interferometry for the particle-emitting source produced in heavy ion collisions at HIRFL-CSR energy. The source evolution is described by relativistic hydrodynamics with three kinds of equations of state for chemical equilibrium (CE), chemical freeze-out (CFO), and partial chemical equilibrium (PCE) models, respectively. We investigate the effects of particle decay, multiple scattering, and source collective expansion on the two-pion interferometry results. We find that the HBT radii of the evolution source for the CFO and PCE models are smaller than that for the CE model. The HBT lifetime for the CFO model is smaller than those for the PCE and CE models. The particle decay increases the HBT radius and lifetime while the source     

共线型声光可调谐滤波器非互易效应研究

通过创建超声频率与衍射效率的动态方程,分析了声光器件在不同射频驱动频率下衍射效率的分布情况,并给出相应表达式.提出了在100 MHz射频处也存在与高于1 GHz处类似非互易现象.进一步通过比例系数δF/ΔF的引入,在此基础上分别利用波长532 nm和632.8 nm激光器,在二氧化碲晶体中进行非互易效应实验.实验得到传输带宽改变达到总衍射带宽的50%～60%,与理论计算值基本吻合.研究结果表明,实际中可将非互易效应大规模应用于包括定向耦合器（光路由器）在内的光电器件的开发.     

与量子输运方程相一致的夸克经典输运方程

用Sμν作为描述夸克自旋的动力学变量建立了它的经典输运方程，并讨论了该方程与量子输运方程的一致性，通过一致性的比较探讨了经典分布函数在色空间和自旋空间的一些特性.