不同激光分布下Nd∶GdVO4晶体热焦距分析

为了研究方形激光晶体Nd∶GdVO4在超高斯泵浦光分布下的热效应,采用半解析的分析方法,进行了理论分析和实验验证.结果表明：当使用输出功率为15 W的半导体激光器端面中心入射时,在抽运端面中心获得1.38 μm最大热形变量（超高斯阶次为2时）和220 mm的热焦距（超高斯阶次为5时）.     

Stereodynamics of the He ＋ D2^＋ → HeD^＋ ＋ D Reaction on the PALMIERI Surface

Using the quasi-classical trajectory method, the product rotational polarization of the ion-molecule reaction He^＋D2^＋ has been calculated at different collision energies on the PALMIERI potential energy surface [Palmieri et al. Mol. Phys. 98 （2000） 1835]. The distribution angle between k and j′, P（Or）, the distribution of the dihedral angle P（Фr）, and the angular distribution of product rotational vectors in the form of polar plots in θr and Фr are calculated. In addition, four polarization-dependent differential cross sections are also presented in the center-of-mass frame, respectively. The results indicate that the rotational polarization of the product HeD^＋ presents different characters for different collision energies. These discrepancies may be ascribed to the different collision energies and constructions of the potential energy surface.     

撞击流中颗粒碰撞传热理论模型研究

建立了考虑颗粒接触面导热的颗粒碰撞传热模型,相应完善了气固两相撞击流理论模型,并对不同条件的撞击流干燥过程进行了模拟。计算结果与实验结果非常吻合,从而验证了所建模型的正确性。本文还分析了颗粒碰撞传热、加料方式以及喷嘴间距对撞击流干燥性能的影响规律。结果表明:在本文所涉及的撞击流干燥过程中,颗粒碰撞传热对干燥性能的影响并不明显;单边加料时颗粒物料的降水幅度及撞击流装置的干燥强度都明显大于双边加料的工况;喷嘴间距较大时,物料的降水幅度及装置的干燥强度均较大。     

基质折射率对反常色散散射体散射特性的影响

基于Mie散射理论,给出了散射强度、散射截面及吸收截面的计算公式,并对不同基质中碳化硅材料在反常色散区中的散射特性进行了数值计算与理论分析。结果表明,在反常色散区中,随着基质折射率的增大,散射强度的峰位发生红移,峰值增大;散射截面和吸收截面的峰位发生红移,峰值减小,这为该材料在反常色散区中的光学理论、实验及应用方面提供了理论参考。     

HIRFL上的中、低能重离子物理基础和应用研究

本文简介HIRFL上中、低能重离子物理基础和应用研究的主要进展;着重介绍三个方面的研究:中能HIC和热核性质的研究,远离稳定线核的合成和研究,重离子束应用,并概述近期实验研究规划的初步建议。 The experimental studies and achievements recently made at the Heavy Ion ResearchFacility of Lanzhou(HIRFL) are reviewed with an emphasis on the three research fields: the study of intermediate energy heavy ion collision and properties of hot nuclei, the synthesis and study of nucleifar from stability, and the applications of heavy ions. A research program for the near future is alsobriefly introduced.     

Hadron spectroscopy from B-factories

We review the recent experimental results on hadron spectroscopy from B-factories focusing on the exotic charmonium-like states.Among them we discuss the X（3872）,Y（3940）,Z（4430） ＋,Z（4050） ＋,Z（4250） ＋ and Y（4140） states found in B-meson decays,the X（3940） and X（4160） states produced in double charmonium production,the Y（4260）,Y（4325）,Y（4660） and X（4630） states produced with initial-state radiation in e ＋ eannihilation and the X（3915）,Y（4350） states observed in two-photon collisions.     

QGP tomography with photon tagged jets in ALICE

γ＋jet events provide a tomographic measurement of the medium formed in heavy ion collisions at LHC energies.Tagging events with a well identified high p T direct photon and measuring the correlation distribution of hadrons emitted oppositely to the photon in ALICE,allows us to determine,with a good approximation,both the jet fragmentation function and the back-to-back azimuthal alignment of the direct photon and the jet.Comparing these two observables measured in pp collisions with the ones measured in AA collisions will reveal the modifications of the jet structure induced by the medium formed in AA collisions and consequently will infer the medium properties.     

核物质状态方程中动量相关作用可能的探针

研究了动量相关作用对于中子-质子比动能谱rb(Ek)的效应,发现rb(Ek)灵敏的依赖于动量相关作用而弱的依赖于介质中核子-核子碰撞截面和对称势.因此rb(Ek)是提取重离子碰撞中动量相关作用信息的可能探针.同时,对于丰中子弹核和相同质量稳定弹核在相同入射道条件下,丰中子碰撞系统明显加强了动量相关作用对rb(Ek)的效应.故两个碰撞系统rb(Ek)结果的比较为在重离子碰撞中提取动量相关作用的知识提供了另一个重要的判据。     

由astroblaster引发的对多体碰撞问题的探究

针对astroblaster多体碰撞过程,运用分离碰撞模型和同时碰撞模型进行分析,对分离碰撞模型给出了计算公式,对同时碰撞模型则进行了计算机模拟.首先,采用刚性分离模型研究二体、三体碰撞物体的运动速度、弹射高度与碰撞体质量之间的关系,得到弹射高度最大化的条件;其次,利用计算机模拟建立同时碰撞模型,研究物体弹性性质对碰撞的影响,分析物体在碰撞时加速度的变化情况,给出在同时碰撞模型下弹射高度最大化的条件.