Self-affine Multiplicity Fluctuation of Slow Particles in 16O-AgBr Collisions at 3.7 A GeV

We study the slow particles in 160-AgBr collisions at 3.7A GeV in nuclear emulsion with the method of twodimensional factorial moments using the Hurst exponent. Our investigation reveals the power law behaviour, exhibited in self-affine analysis, better than that in self-similar analysis. This work shows a clear evidence of self-affine target fragmentation.     

利用ICCD定位宇宙线来测量探测器时间分辨的方法研究

本研究采用双层150 mm×150 mm闪烁条阵列定位宇宙线的入射和出射位置. 阵列信号光使用波移光纤吸收传输,在ICCD相机前插入前置像增强器,使信号光延迟大于200 ns, 使ICCD可以由外部高速触发信号控制,有效记录随机触发事例.该宇宙线定位系统可以同时多点密集测量 通用探测器测试平台的时间分辨和闪烁光的渡越时间.该新方法与传统时间分辨测量方法相比提高了30倍以上 的效率.实验结果显示:时间探测器的时间分辨好于200 ps,满足通用探测器测试平台的设计要求.     

热核多重碎裂中的条件矩与核内液气相变信号

评述和研究了热核多重碎裂中的条件矩关联与分布，并讨论了核内液气相变的信号． The conditional moment correlations and distributions in hot nuclear multifragmentation are reviewed and investigated. The signals of liquid gas phase transition in nuclear matter are discussed.     

分子马达的三态周期跳跃模型

研究了在一维三态周期跳跃模型下分子马达的定向运动.对于给定的任意初始分布,得出了与时间有关的几率分布的解析表达式,包括到达稳态之前的所有的瞬态过程,由此可获得马达在各个时刻的漂移速度v、扩散系数D以及描述马达随机性质的随机参数r(randomness parameter ).同时还计算了马达到达稳态所需要的特征时间.并把计算结果同实验进行了比较.     

Event patterns extracted from top quark-related spectra in proton-proton collisions at 8 TeV

We analyze the transverse momentum(p _T)and rapidity(y)spectra of top quark pairs,hadronic top quarks,and top quarks produced in proton-proton(pp)collisions at center-of-mass energys~(1/2)=8 Te V.For p _(T )spectra,we use the superposition of the inverse power-law suggested by the QCD(quantum chromodynamics)calculus and the Erlang distribution resulting from a multisource thermal model.For y spectra,we use the two-component Gaussian function resulting from the revised Landau hydrodynamic model.The modelling results are in agreement with the experimental data measured at the detector level,in the fiducial phase-space,and in the full phase-space by the ATLAS Collaboration at the Large Hadron Collider(LHC).Based on the parameter values extracted from p _(T )and y spectra,the event patterns in three-dimensional velocity(β_x-β_y-β_z),momentum(p_x-p_y-p_z),and rapidity(y_1-y_2-y)spaces are obtained,and the probability distributions of these components are also obtained.     

PSEUDORAPIDITY DISTRIBUTIONS OF RELATIVISTIC SINGLY CHARGED PARTICLES IN HIGH ENERGY NUCLEUS-NUCLEUS COLLISIONS

The pseudorapidity distributions of relativistic singly charged part icles produced in high energy nucleus-nucleus collisions are described by the thermalized cylinder picture. The calculated results are in agreement with the recent experimental data of gold induced interactions at the Brookhaven National Laboratory.     

重离子熔合势垒的动力学模型研究

在改进的量子分子动力学模型基础上系统地研究了超重核合成中的入射道静态势和动力学势.从入射道静态势给出了质量不对称度与静态势垒高度以及质量不对称度与接触点驱动势的关系.动力学势垒高度是能量依赖的,随着入射能量的增加而增加,最终趋近于密度冻结势垒高度;动力学势垒高度随着入射能量的降低而降低,它的最低值接近于绝热势垒高度.在冷熔合反应中,动力学势垒的最低值所对应的入射能量可能是合成超重元素最佳入射能的选择     

相对论性重离子碰撞中负粒子的横动量和赝快度分布

基于三火球模型和强子共振态衰变图象,得到了相对论性重离子碰撞中负粒子的横动量和赝快度分布,并与200和60GeV/N ¹⁶O与An相互作用的有关实验结果作了比较.     

Various flows of black and grey particles produced in Mg-emulsion collisions at 4.5 A GeV/c

Various flow phenomena of black particles (b-particles) and grey particles (g-particles) produced in magnesium-emulsion (Mg-Em) collisions at 4.5 A GeV /c are reported. These flows are directed and elliptic transverse flows (v₁ and v₂) related by the azimuthal angle (φ), directed and elliptic reaction plane flows (v_R1 and v_R2) related by the projected angle (ψ) on the reaction plane, and directed and elliptic polar direction flows (v_P1 and v_P2) related by the polar angle (θ). We extract absolute flows as the direct experimental values minus the isotropic theoretical values. The dependence of the various flows on the target particle multiplicity and on the angles (θ,φ,ψ) is investigated. Our results show that the dependence of b-particle flows on the target size is obvious and for heavy targets the dependence on target particle multiplicity is slight. Compared with b-particles, g-particles have a slight dependence on the target size and target particle multiplicity.