1991 Vol. 15, No. 3

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The Beam Optics of Electric Multipole Lens
HU Nai-Xiong, XIMEN Ji-Ye
1991, 15(3): 193-199.
in this paper,the beam optics of an electric multipole lens containing aberrations is established,the aberration matrix is derived,and its determinant is shown to be unit.When the beam travels through an electric multipole lens and the aberrations exist,the electron beam theory for ellipsoid in phace space is still valid.
Magnetic Axis Measurement in the Solenoid of Beijing Spectrometer
ZHANG Ge, ZHU Shan-Gen, ZHOU Yong-Shen, ZHAO Meng, ZHAO Di-Xin, LI Jia, HAN Shi-Wen, FU Zheng-Shan
1991, 15(3): 200-206.
This paper discusses the basic principle of the magnetic axis measurement on the magnetic field of the solenoid magnet for BES,the measuring method as well as the result.
Non-Pertubative Correction to R=σLT Due to the Effect of the QCD Vacuum Condensates
DAI Yu-Xin, QIU Zhong-Ping
1991, 15(3): 207-212.
The effects of QCD vacuum condensate on hardron structure function are considered.Based on the background field theory,starting from the effective lagrangian of QCD we calculate the non-perturbative correction to ratio R=σLT of the hardron structure function.Our corrections are sensitive at small x regions.
The One Loop Calculation of the Strong coupling β Function in the Toy Model
BAI Zhi-Ming, JIANG Yuan-Fang
1991, 15(3): 213-219.
In this paper,the background field quantization is used to calculate the one-loop β function in the Toy Model which has the strong coupling and the SU(3) symmetry.the function obtained is consistent with the Appalquist-Carrazone theorem in the low energy condition.
Negative Particle Rapidity Distribution in Relativistic Heavy Ion Collisions
LIU Bo, ZHAO Wei-Qin
1991, 15(3): 220-223.
Particle production process in nucleon-collisions is described in two fireball model.The negative particle rapidity distribution data of NA35 are fitted very well by nuclear collision geometry.The strong relation between n-(b) and b is found.
The η-N Interaction Potential and the Potential Well Depth of η-meson in Nuclear Matter
LIU Ji-Feng, WU Pei-Yun, SHEN Jian-Ping, LI Guang-Lie
1991, 15(3): 224-233.
In this paper,the η-N interaction potential via the Channel:N*ηN is derived within the framework of quantum field theory.By using this η-N S wave scattering length and the potential well depth of η-meson in nuclear matter are calculated.It is shown that the theoretical value of the η-N S wave scattering length is in good agreement with that obtained by analysing the πN scattering experimental data and our computational result for the potential well depth of η-meson in nuclear matter is about the same as other theoretical predictions for finite nuclei.
Beam Optics Principle of the ISOLAN Facility
HUANG Ye-Cheng
1991, 15(3): 234-239.
According to the theory of charged particle transportation the beam optics principle of the ISOLAN facility was deduced.The basical parameters and the layout of the facility were also described.
Microscopic IBM-2 Description of the Phase Transition of Nuclear Spectra Near A=130
ZHAO Xiao-Feng, LI Xian-Yin
1991, 15(3): 240-244.
The phase transition of low-lying energy spectrum structure for Ba isotopes and Sm isotopes are studied in the framework of microscopic IBM-2 based on the boson expansion.It seems possible to describe the phase transition in a unified way within the approach.
Staggering Phenomenon in Nuclear Energy Spectrum and Quadrupole-Quadrupole Interaction
LIU Yu-Xin, LONG Gui-Lu, SUN Hong-Zhou
1991, 15(3): 245-250.
An improved treatment on staggering phenomenon in nuclear energy spectrum in the framework of IBM2 is described in this paper, The hamiltonian is introduced to treat the even-even isotopes of Ru and Pt.The relation between the staggering phenomenon and the quadrupole-quadrupole interaction is discussed.
Theoretical Researches on α-transfer Rates of Ground States in Medium and Heavy Nuclei
REN Zhong-Zhou, XU Gong-Ou
1991, 15(3): 251-255.
The α-transfer rates of ground states in medium and heavy nuclei are obtained analytically in a two-level pairing force model of j-j scheme.It is concluded that,like the pair-transfer,there is a blocking effect in α-transfer reactions because of the single and unpaired nucleon. This is accordance with the experimental facts.
1/N Expansion Technique and the Non-SU(3) Intrinsic States of the sdg Interacting Boson Model
WU Hua-Chuan, RONG Zhong-Lin, WANG Zhen
1991, 15(3): 256-264.
By utilizing the 1/N expansion technique,the SU(3)-symmetry breaking caused by boson energies is discussed for the sdg Interacting Boson Model,and the analytical expressions of the intrinsic states are given under the approximation in the order of 1/N.It is also shown that the many body theories for a interacting boson system,such as Hartree-Bose method.Tamm-Dancoff approximation and Cranked Hartree approximation,are all special cases of the 1/N expansion technique.
J/ψ Physics at BEPC and the Generalized Moment Analysis
YU Hong
1991, 15(3): 265-278.
Three million J/ψ events have been obtained at Beijing Electron and Positron Collider (BEPC) and Beijing Spectrometer (BES) by Aug.1990 and some preliminary analysis have been performed.It is expected that 1—2×107 J/ψ events will be accumulated during 1991 In this paper we give a review about some new hadron states which may appear in J/ψ decays and how to determine the spin-parity of these new hadron states by using the generalized moment analysis.
Calculation of Nuclear Fission Using a Macroscopic Model
CHEN Xin-Yi, HU Ji-Min
1991, 15(3): 279-283.
The continuous medium model with variable densities is used to calculate the macroscopic potential energy surfaces of β-stable nuclei with A≥100.The reasonable fission barriers are obtained and the double mass center charge distributions of fissioning nuclei at saddle points are predicted.
S-D Mixing and Electric Dipole Transition of ψ(3770)
QIN Dan-Hua, DING Yi-Bing, ZHAO Guang-Da
1991, 15(3): 284-288.
In the framework of the potential model for charmonium,the effects of 23S1-13D1 mixing between ψ(3770) and ψ(3686) are discussed.It is concluded that the possibility for the mixing angle θ=30° should be ruled out.While the results for both ψ(3770)→γχ0 and ψ(3686)→γχ0 are improved with θ=-10°,the contradiction between the theoretical value and the experimental value for ψ(3770)→γχ1 still remains.