1989 Vol. 13, No. 2

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Review
GAMMA FAMILY EVENTS WITH LARGE-SEPARATION DOUBLE CORES
REN Jing-Ru, HUO An-Xiang, LU Sui-Ling, SU Shi, WANG Cheng-Rui, ZHANG Nai-Jian, CAO Pei-Yuan, LI Jin-Yu, ZOU Bao-Tang, WANG Shi-Zhi, GENG Qing-Xi, BAI Guang-Zhi, MU Jun
1989, 13(2): 97-102.
Abstract:
A peculian cosmic ray double core event K5618 was recently found in Mt.Kanbala emulsion chamber,with the following characteristic quantities:zenith angle=27°,total visible energy ΣEγ=547TeV;energies of the two cores E1=428TeV and E2=119TeV with the separation between them R12=25.56cm.it is expected that such an event might give some indication of the signal of the production of extraordinarity large transverse momentum particles in super high energy hadronic interactions.
SEARCH FOR SUPERHEAVY NUCLEARITES IN METEORITES BY RUTHERFORD BACKSCATTERING
LIU Shi-Jie, XIE Bao-Zhen, WU Yue, TANG Xiao-Wei
1989, 13(2): 103-105.
Abstract:
An experiment to search for stable superheavy nuclearites and quark nuggets in different meteorites has been performed using the Rutherford backscattering technique.The upper limit of the relative concentration of nuclearites with Z≈100,A≈1000 in the meteorite samples about 2ppm is obtained.
A DISCUSSION OF TRANSFORMATIONS OF STRIP ION BEAMS INTO AXISYMMETRICAL BEAMS
YU Qing-Chang
1989, 13(2): 106-108.
Abstract:
In this paper,the methods for transforming strip ion beams into axisymmetrical beams with given focusing properties by means of thin quadrupole lenses,axisymmetrical thin lenses and deflecting magnets are discussed.
A CLASSICAL MODLE OF QUANTUM BERRY'S PHASE FACTOR
SUN Chang-Pu
1989, 13(2): 109-115.
Abstract:
Considering that the classical evolution equations are similar to the Schrodinger eqaution,we point out that there is the structure of the Berry's Phase in the solution of a classical evolution eqaution with adiabatic changing parameters.Thus,we can use a classical evolution process to imitate the quantum adiabatic process.As an example,the motion of a charged particle in slowly-changing magnetic field is studied and the corresponding phase factor can be interpreted as a holomony of the fiber bundle on the sphare s2 in the parameter space.
OCTUPLE DEFORMATION EFFECT IN PION SCATTERING FROM WELL-DEFORMED NUCLEI
HUANG Chao-Hui, JIANG Huan-Qing
1989, 13(2): 116-119.
Abstract:
The importance of octuple deformation in π±-152Sm scatterings is studied.Results show that the contribution due to octuple deformation to the differential cross section is small.
SYMMETRIES OF CONFORMAL TRANSFORMATION FOR SPECTRAL PARAMETER
HAO San-Ru, LI Wei
1989, 13(2): 120-127.
Abstract:
The symmetry of O(3) non-linear sigma model under a dual transformation is discussed and the origin of the transformation of generating functions is explored;Existence of the infinite dimensional symmetries is confirmed.We obtain the infinite dimensional Lie algebraic structure of the basic fields and the semi-product algebraic relation of the two kinds of algebra.The corresponding Bianchi-Backlund transformations are given.
πN SCATTERING PHASE SHIFTS IN A MODIFIED SKYRME MODEL
SHEN Qi-Xing, LI Bing-An
1989, 13(2): 128-134.
Abstract:
The P-wave phase shift of πN scattering and the mass and width of the Roper resonance are computed in a modified Skyrme model.The results are better than those calculated from the original Skyrme model.
THE NONABELIAN BOSONIZATION OF FERMION FIELDS IN (1+1) DIMENSIONS BY PATH INTEGRAL METHOD
NI Guang-Jiong, WANG Rong-Tai, CHEN Su-Qing
1989, 13(2): 135-141.
Abstract:
Using the path integral method for handling the anomaly problem under the comoving representation,we present a unified scheme for deriving the bononization of fermion fields in (1+1) dimensions.The massless Thirring model with an external electric field,and the Gross-Neveu model with internal SU(N) symmetry,as two examples for abelian and nonabelian bosonization,are discussed repectively in some detail.
ON THE BEHAVIOR OF PHASE TRANSITION SHOWN IN DISASSYMBLY PROCESSES OF VERY HOT AND DILUTE FINITE NUCLEAR SYSTEMS
SA Ben-Hao, ZHENG Yu-Ming, ZHANG Xiao-Ze, LU Zhao-Qi, XU Shu-Yan
1989, 13(2): 142-147.
Abstract:
The behaviors of phase transition shown in disassymbly processes of very hot and dilute finite nuclear system have been exposed by using canonical (microcanonical) ensemble Monte Carlo simulation.It is explained that they result from the competition between Coulomb interaction and the effect of finiteness.
RELATIVISTIC STUDY OF PROTON-NUCLEUS ELASTIC SCATTERING AT LOWER ENERGIES
LI Yang-Guo
1989, 13(2): 148-155.
Abstract:
The Lorentz invariant relativistic optical potential have been discussed at energies below 300MeV.The Dirac equation with scalar and vector potential is solved by exact partial wave method.The calculated results of proton 40Ca at energy region 300—65MeV are presented and compared with the experimental data of differential cross section dσ/dΩ,analyzing power Ay(θ) and spin rotation function Q(θ).It is shown that the impoved relativistic optical potential fits the data well.
THE POSSIBILITY OF EXITENCE OF NEW ISOTOPE 65Se
XU Xiao-Ji
1989, 13(2): 156-163.
Abstract:
A new beta-delayed proton precussor 65Se has was probably produced via the reaction 40Ca (28Si,3n)65Se and identified from its beta-delayed proton emission.A single proton group at 3.75±0.05MeV with half-life of 10.8±4.1/3.7ms was observed,corresponding to superallowed beta decay of 65Se to the isobaric analog state of 65As (the lowest T=3/2 state in 65As) then proton emitting to the ground state of 64Ge.Because of poor statistics further experimental effort is required to confirm this discovery.
EFFECT OF NUCLEAR VISCOSITY ON FISSION PROCESS
LI Shi-Dong, KUANG Hui-Shun, ZHANG Shu-Fa, XING Jing-Ru, ZHUO Yi-Zhong, WU Xi-Zhen, FENG Ren-Fa
1989, 13(2): 164-172.
Abstract:
According to the fission diffusion model,the deformation motion of fission nucleues is regarded as a diffusion process of quasi-Brownian particles under fission potential,Through simulating such Brownian motion in two dimensional phase space by Monte-Carlo method,the effect of nuclear viscosity on Brownian particle diffusion is studied,Dynamical quantities,suchas fission rate,kinetic energy distribution on scission,and so on are numerally calculated for various viscosity coefficients,The results are reasonable in physics,This method can be easily extended to deal with multi-dimensional diffusion problems.
STUDY OF ASSOCIATED GAMMA RAY FROM NIOBIUM UNDER 14.9MeV NEUTRON BOMBARDMENTS
ZHOU Hong-Yu, YAN Yi-Ming, FAN Guo-Ying, LAN Li-Qiao, SUN Shu-Xu, WANG Qi, HAN Ming, HAN Chong-Zhan, LIU Shu-Zhen, RONG Ya-Ning, WEN Chen-Lin, WANG Xin-Fu, YANG Hua, WANG Wan-Hong, TANG Lin
1989, 13(2): 173-183.
Abstract:
The gamma ray spectra from niobium under 14.9MeV neutron bombardments were neasured by means of a pulsed T(d,n)4He neutron source,associated particle method,Ge(Li) detector and time-of-flight technique at 7 angles between 30°and 140°.79 gamma lines were determined by a high resolution gamma spectrum analysis program,and reaction types and transition levels of 62 lines were rudely assigned.There were 40 ones of 79 lines,which were first found in reactions induced by neutrons.The differential cross sections of every gamma line at 7 angles were determined.It is shown that associated gamma ray emission from this reaction are basically asotropic.
THE VARIATIONAL CALCULATION OF MASS GAP IN 2+1 DIMENSIONAL U(1) LGT
ZHENG Wei-Hong, GUO Shuo-Hong
1989, 13(2): 184-187.
Abstract:
We present a variational calculation of 0+- and 0++ glueball masses in 2+1 dimensional U(1) lattice gauge theory by using a Hamiltonian which possesses exact ground state and correct classical continuum limit.In deep weak coupling region,we obtain that am(0+-) decreases with 1/g2 exponentially and am(0++)=2.78g2.
β FUNCTION FOR SU(2)×SU(2) CHIRAL MODEL ON 2-DIMENSIONAL RANDOM TRIANGLE LATTICE
CHEN Tian-Lun, HUANG Wu-Qun, JIN Ke, SUO Cun-Chuan
1989, 13(2): 188-192.
Abstract:
The β function behavior for SU(2)×SU(2) chiral model on 2-dimensional random triangle lattice has been studied with Monte Carlo renormalization group method.Its behavior is similar to that of the 4-dimensional SU(2) gauge theory.However,it is smoother from weak to strong coupling regions.There is no nonperturbative peak structure.The asymptotic scaling starts beyond β=1.6.