封底照片说明

北京时间2011年5月16日晚8点56分,美国"奋进号"航天飞机升空,开始了其谢幕之旅。"奋进号"航天飞机此次行动,搭载了用于寻找反物质宇宙以及暗物质来源的阿尔法磁谱仪2,这是继人类基因组计划、国际空间站计划、大型强子对撞机计划后又一大型国际科技项目。中国科技人员参与了阿尔法磁谱仪的研制工作。据阿尔法磁谱仪首席科学家丁肇中表示,目前磁谱仪工作良好,其成果很令人期待。     

JLab 及其物理研究

高能轻子与核子的相互作用是研究强子物理的主要手段。美国JLab(Thomas Jefferson NationalAccelerator Facility)实验室以其CEBAF(ContinueElectron Beam Accelerator Facility)加速器提供的优良性能的电子束(高的能量分辨率、小的束斑、大的流强和高达85%的极化度)和三个实验厅中建有的高精度谱仪成为世界上研究强子物理的重要基地。     

强子结构函数的数值解法

为了避免矩方法求解强子结构函数时对函数待定形式的依赖并提高解的精确度,本文采用把A-P方程离散为常微分方程组,用龙格-库塔方法求解的方法,得出随Q²变化的价夸克、海夸克和胶子的结构函数。     

三角奇点与XYZ类粲偶素结构

对强子谱的研究有助于加深量子色动力学中色禁闭现象的理解。强子谱中存在诸多疑难问题,特别是2003年以来各高能物理实验上发现了很多难以理解的新的强子共振结构,其中大量是在重夸克偶素质量区间发现的,它们被统称为$XYZ$结构。强子共振态对应于$S$矩阵的极点。除此之外,$S$矩阵还具有其它类型的奇点,比如由于三个中间态粒子同时在 壳导致的三角奇点。本文中,我们将讨论三角奇点在$XYZ$物理中的实现,注重于构造可以用来分析 其对$e^+e^-\to\psi\pi^+\pi^-$反应的$\psi\pi$不变质量谱中的带电$Z_c$结构的影响的振幅。     

相对论重离子碰撞中强子气体膨胀过程的蒙特卡罗研究

利用AMPT蒙特卡罗产生器中的强子化程序模块ART1.0, 得到了强子化过程的演化图形, 并基于强子在不同时刻的空间分布图, 估算出了不同时刻的反应区域半径. 将所得结果与根据HBT关联得到的结果相比较, 定出了冻结为强子气体的时刻, 得到了合理的结果.     

eμ Production in R-Parity Violating Supersymmetric Model at Hadron Colliders

We investigate the lepton flavor violating productions pp/pp→eμ ＋ X in the framework of the R-parity violating （RPV） supersymmetric model at the Tevatron and the CERN large hadron collider （LHC）. We present the total cross sections including the next-to-leading order （NLO） QCD corrections and the contribution from gluon-gluon fusion subprocess. Our numerical results show that the one-loop QCD corrections significantly increase the tree-level cross sections, and the variation of K factor is in the range between 1.28 （1.32） and 1.79 （1.58） at the Tevatron （LHC）. We find that the QCD correction from the one-loop gluon-gluon fusion subprocess is remarkable at the LHC and should be taken into account.     

发现量子宇宙——粒子对撞机的角色

 当今正是粒子物理学发生根本性变革的时期。新近的实验证据要求一种全新的宇宙图像。一些新的发现近在咫尺，它们将以新的物质形态、新的自然力和新的时空维度来拓展人们的想像力。突破将来自下一代粒子加速器，即目前正在欧洲建造的大型强子对撞机(LHC)，以及拟议中的国际直线对撞机(ILC)。在这些加速器上进行的实验将使你的宇宙观念发生根本性的变革。     

序言

Since the announcement of the discovery of a ＂perfect liquid＂ at the Relativistic Heavy Ion Collider （RHIC）, significant progress has been made towards understanding the details of the property of the matter that RHIC has created. Yet there are still puzzles and unsolved problems. At frontiers from other accelerator facilities like Gesellschaft fur Schwerionenforschung, German （GSI） and the Heavy Ion Cooler Storage Ring at institute of Modern Physics, China （CSR）, which are to understand the structure and behavior of the world that surrounds us -- a mission that is similar to RHIC but with different aspects, upgrade plans are on-going and hopefully they will open horizons for potential new discoveries. To promote and facilitate interactions amongst scientists from both experiments and theory, and to enhance the direct exchange of scientific information amongst scientists from both Hadron physics and Heavy Ion physics, the ＂International Workshop on Hadron Physics and Property of High Baryon Density Matter＂ was held in Xi＇an during Nov. 22 to Nov. 25 as a satellite meeting of QM 2006.     

双束加速器

本文介绍了在TeV能量区域电子一正电子直线对撞机的进展和双束加速器研究的概况。着重介绍以自由电子激光作微波功率源和用激励加速器作微波功率源的二种双束加速器。     

HepMC＿Contrib：Persistent Interface Package for HepMC

A persistent interface package Hep MC_Contrib is developed for the C Monte Carlo event class library HepMC.HepMC_Contrib package provides an interface to user programs for storing /retrieving HepMC event records to/from Objectivity database,HepMC_Contrib is designed to utilise the standard features of HepODBMS as much as possible,Two types of implementation of class design were tested to reduce the size of the database,At last,the performance of the package is discussed in terms of the size of database.