HEAVY ION RESEARCHES IN LANCHOW

Since the middle of 1972,we have been carrying out a research programme in the field of heavy ion physics.A series of preliminary experiments have been done.Some typical examples are illustrated in this paper.     

用电阻法确定裂纹扩展的开裂点

近几年来,为了解决弹塑性体的断裂判据,提出了“COD”方法和J积分方法等。用实验测量其临界值的关键是需要确切地判断裂纹开始扩展的开裂点。 目前已发展了多种方法(如声发射、电位法、柔度法和金相法)以确定开裂点。我们研究了一种比较能确切判断开裂点的电阻法。     

THE SYMMETRY OF STRATONS IN

In this paper,the color symmetry of stratons for a theoretical model proposed some times ago is investigated.This symmetry contains two kinds of transformations, the first is color gauge transformations which leave the color mumber of stratons conserved,the second is color permutations which indicate the equivaluence of dif- ferent color stratons.The structure of this symmetry group（S3α）is investigated.The irreducible representations（IR's）of S3α and the reduction of their direct product are given.The relation between IR's of S3α and those of color U（3）group is discussed. In a simplest physical model only two neutral vector gluons are needed and the super-strong ihteraetions among stratons exhibit saturation properties similar to but somewhat different from the case of the Han-Nambu model.Not only the color singlet, but also other color neutral states belonging to IR's 2 or 1 of S3α all belong to the lowest energy level of the super-strong interactions.If there were eight degenerate vector gluons belonging to IR's 2 and 6,the Han-Nambu model would be reproduced.     

AN SU（4）×S3a SCHEME OF THE STRATON MODEL

In this paper, we propose an SU（4）×S₃^a scheme of the Straton Model and discuss the classification of mesons. We suggest the possible existence of several colour excited states with masses around 2 GeV in companion with charm mesons. We also discuss the properties and the experimental behavior of these colour excited states, especially, the possible contribution of these states in several new phenomena.     

ELASTIC SCATTERING OF FAST NEUTRONS FROM Fe,Cu AND Pb

Using time of flight technique the elastic differential cross sections were measured for neutrons from natural Fe, Cu, and Pb in the energy range 1.10 to 1.40 MeV.The effect of neutron attenuation and multiple scattering in the sample is corrected by extrapolation of the experimental results. The correction of scattering angles due to the finite source-sample-detector geometry is also considered. The measured elastic differential cross sections are expressed by Legendre polynomial expansions, from which the total cross sections are obtained.The Optical-Model Calculations are carried out which show a reasonable consistency with the measured values.