1999年 第16卷 第1期
概要介绍了超形变核态的相互作用玻色子模型研究的现状、理论框架及一些应用.The present status, the framework and some applications of the investigation on the superdeformed nuclear states in the scheme of the interacting boson model are described.
在原子核的代数模型框架下，讨论了集体回弯效应、较高自旋的Ｆ－旋混合对称态以及电磁跃迁几率等问题． The collective backbending effect, F spin mixed symmetry states have been studied for the nuclei with moderate high spins. It is found that there is an additional L(L+3) proportional term in the E2 transition rates in the sdg interacting boson model and solved the long standing problem of reduction of collectivity in the wave function of boson models. The electromagnetic transitions in the spdf interacting boson model have been calculated and compared with existing experimental...
利用不可约张量基的概念和不可约张量算符的性质，给出了所有Ｏ（Ｎ）Ｏ（Ｎ－１）约化因子（ｍ１Ｎｍ２Ｎ…ｍ［Ｎ／２］Ｎ）（１０…０）的代数表达式． The algebraic expressions for all O(N) O(N-1) reduction factors for (m 1N m 2N … m N ) (1 0 … 0) are given by using the concept of irreducible tensor basis and the properties of irreducible tensor operator.
对近年来清华大学现代应用物理系开展的原子核结构实验研究的情况作了介绍，着重对所研究过的核高自旋态（包括个别核的低自旋态）结构特性进行了简述．The experimental research on nuclear structure in Department of Modern Applied Physics, Tsinghua University has been summarized. The main research results in high spin states of nuclear structure, as well as some low spin states, have been reported.
介绍了通过测量重核裂变产生的瞬发γ谱方法，对围绕Ｚ＝５６、Ｎ＝８８丰中子核区高自旋态八极形变的研究，并对Ｘｅ、Ｂａ、Ｃｅ和Ｌａ等丰中子核链的八极形变特性进行了讨Through study of the prompt γ rays in spontaneous fission, the octupole deformation in neutron rich Xe, Ba, Ce and La isotopes around Z =56, N =88 region was assigned. The properties of the octupole deformation in these nuclei were also discussed. 论．
快中子核反应数据，不论对反应堆和聚变堆的设计，还是对核反应机制和核结构的研究及其理论的发展均有着重要的意义．由于屏栅电离室的诸多特点，被用于快中子核反应截面、能谱及双微分截面的测量．作为系统研究的一部分，利用屏栅电离室在北京大学４．５ＭＶ静电加速器上和在４～７ＭｅＶ能区内，对４０Ｃａ、６４Ｚｎ、５８Ｎｉ、５４Ｆｅ、３９Ｋ的（ｎ，α）反应进行了成功的测量，并对５８Ｎｉ的（ｎ，ｐ）反应进行了初步的测量．实验给出了反应中出射粒子的微分能谱、角分布和反应截面．从测量结果来看，在所测能区内，角分布大致是９０°对称的，说明在此能区复合核反应机制起主要作用．The study of the charged particle emission reactions induced by 3～7 MeV fast neutrons is of considerable interest for both nuclear applications and the understanding of basic nuclear problems. For its many merits, twin gridded ionization chamber is used in the studies of (n,α) and (n,p) reactions. As a part of systematic investigation, the (n,α) reactions for some nuclei, such as 40 Ca, 64 Zn, 58 Ni, 54 Fe, 39 K have been studied. Cross sections...
仔细评价并介绍了几个可在核数据工作中直接应用的中重核色散光学模型参数．By careful analysis, the parameters of DOMA (Disperse Optical Model Analysis) for some medium and heavy nucleus are determined. These parameters are useful for the evaluation of nuclear data.
对２０８Ｐｂ的低激发态分立能级属性和相关平均振幅或形变参数进行了系统研究，利用扭曲波波恩近似方法系统计算了１２个分立能级的中子直接非弹性散射截面． The amplitudes or form factors of the low discrete levels of 208 Pb are investigated systematically, the neutron direct inelastic scattering cross sections from 12 levels on 208 Pb are calculated.
简单介绍了极化电子束的获得，即极化电子源，讨论了对电子束极化度的测量，极化电子与原子散射，以及极化电子束在固物理、生物物理、核物理与粒子物理中的应用． The getting of polarized electrons was briefly introduced, that is the source of polarized electrons. The measurement of polarization in future, the application of polarized electrons in atomic and molecular physics, condensed physics, biological physics, nuclear and particle physics were discussed.
简要介绍了圆偏振激光在极化电子束上的Ｃｏｍｐｔｏｎ散射理论，研究了北京正负电子对撞机（ＢＥＰＣ）极化仪的测量原理，并根据ＢＥＰＣ极化仪的实验参数计算了散射的能谱、空间分布和强度．The theory of Compton scattering of polarized photons on polarized electrons, and the principle of Beijing Electron Positron Collider (BEPC) Compton polarimeter are shortly discussed. The energy spectrum, vertical distributions and the intensity of Compton scattering under particular conditions are also calculated.
概述国际上一些新型闪烁晶体的研究状况，重点介绍对ＢａＦ２和ＰｂＷＯ４闪烁晶体性能及其应用进行研究所取得的一些结果．The status of the study on some new scintillators is summarized, and the results of our researches on the properties and applications of BaF 2 and PbWO 4 crystals are discribed.
综述伴随粒子成像技术的基本原理、主要性能和研究进展．伴随α粒子方法可以实现位置灵敏，可以用于需要位置灵敏的检查中，如机场隐蔽爆炸物的检查和毒品的检查，有着重要的应用前景． The basic principles, important characteristics and recent progress of associated particle imaging were reviewed. Associated particle imaging is position sensitive. It can be used in position sensitive examinations, for instance, hidden explosive inspection in airfield custom examination, drug examination. It has an important perspective in application.