1986 Vol. 10, No. 5

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Review
THE ACCURATE DETERMINATION OF SMALL VARIATIONS FOR THE PARAMETERS OF POSITRON LIFETIME SPECTRA IN AMORPHOUS ALLOY
XIONG Liang-Yue(L.Y.Xiong)
1986, 10(5): 513-518.
Abstract:
The method for the accurate determination of the small variation of positron lifetime spectrum parameters is described by the example of determining the positron lifetime variations by means of annealing in amorphous material. The comparison between the differential distributions by simulation calculation and by experimental measurement comfirms that the mean positron lifetimes in metallic glass Fe67Co18Si1B14 after annealing at 200℃,300℃ and 375℃ are 0ps, 4.0ps and 4.3ps, respectivly, shorter than that in the nontreated reference sample.
PLASTIC SCINTILLATOR RESPONSE TO CHARGED PARTICLES
ZHOU Da-Zhuang
1986, 10(5): 519-526.
Abstract:
Plastic scintillators with many advantages are widely used in particle physics. Researches on plastic scintillator response at both high energy and high electric charge are significant to the experiments in high energy physics and cosmic ray physics. In addition to many important astrophysical results, the high energy cosmic rays experiments at the University of Chicago accumulate data for plastic scintillator response to relativistic particles of high electric charges. This paper introduces the cosmic ray experiments mentioned above, presents data analysis results and the discusses the nonlinear response of plastic scintillators.
THE BETHE-SALPETER EQUATION FOR SPIN (0—3/2) ELECTROMAGNETIC BOUND SYSTEM AND ITS APPROXIMATE SOLUTION
DAI You-Shan, SONG Xiao-Tong
1986, 10(5): 527-535.
Abstract:
In this paper. the Bethe-Salpeter equation for spin (0—3/2) electromagnetic bound system is derived. Under the ladder approximation the approximate B-S wave function with accuracy up to order 0(α) for this system is obtained. Utilizing this wave function, we estimated the cross section for producing (π+Ω) in Ω-p collision process.
THE BEHAVIOR OF PARTONS OF LARGE TRANSVERSE MOMENTUM IN DEEP INELASTIC SCATTERING
WANG Zheng-Ben
1986, 10(5): 536-544.
Abstract:
The nucleonic states are represented by different configuration components in Fock space and the transverse momentum of partons is introduced as a degree of freedom into the structure function. In this way We calculated the contribution of the components of the valent quarks and the non-valent quarks of the charm state to the ratio of the longitudinal and the transverse cross sections of the virtual photons. A better agreement with the experimental data is obtained. The causes of deviation of the Callan-Gross relation from the experimental data is pointed out.
ON THE SUPERHEAVY FERMION——SO(10) MONOPOLE ZERO-ENERGY BOUND STATES
QI Yong-Chang
1986, 10(5): 545-552.
Abstract:
It is found that the zero-energy bound state of the superheavy fermion and SO(10) Monopole is possible. As a result we conclude that the Rubakov effect may exist in the presence of superheavy fermions.
APPLICATION OF THE FF MODEL TO PROTON-PROTON SOFT COLLISION
CHEN Zhi-Jiang, LIU Han-Zhao
1986, 10(5): 553-561.
Abstract:
We applied the FF model of the quark-jet to the proton-proton soft collision and suggested a scheme for the diquark fragmentation. In this way we improved the two-chain model. The improved model not only can give the mean yields of various particles (such as meson, baryon, photon, quark-pairs, etc.) but also can calculated the single particle distributions and the correlations. The results are in agreement with experiments.
A POSSIBLE FORM OF THE PION'S STRUCTURE FUNCTION
LONG Ming, HUANG Tao
1986, 10(5): 562-569.
Abstract:
The pion's structure function behaviour is discussed by using the Fock state expansion of the hadronic wavefunction in QCD in this paper. As an example, we employ a model wavefunction of the Fock state in the light-cone and assume a Regge behaviour of a weight function for higher Fock states, and we get a possible form of the pion's structure function. This form is consistent with experimental data of the pion's structure function.
PION-SCATTERING FROM VIBRATIONAL NUCLEUS
ZHANG Yu-Shun, JIANG Huan-Qing
1986, 10(5): 570-577.
Abstract:
We calculate the angular distributions of elastic and inelastic scatterings from vibrational nuclei by using optical potential. The neutron and proton transition densities can be studied by comparing the π+ and π scattering on the nucleus. The importance of the virtual excitation of vibrational levels in calculating the differential cross section is discussed.
THE EDDY-CURRENT EFFECTS OF A BENDING MAGNET ON AN ELECTRON STORAGE RING DURING SLOW ACCELERATION
PEI Guo-Xi, ZHANG Wu, TIAN Bao-Ying, XU Jian-Ming
1986, 10(5): 578-582.
Abstract:
The magnetic field distribution of a C—type solid yoke bending magnet—a model magnet used on the Hefei synchrotron is measured and the eddy-current effects of a bending magnet on an electron storage ring during slow acceleration are investigated by two coil induction approach. When slow acceleration exists, possibility of applying a solid yoke bending magnet is verified.
ANALYSIS FOR ENERGY SPECTRA OF LIGHT PARTICLES EMITTED FROM 12C+64Ni REACTION
ZHANG Li, JIN Gen-Ming, WANG Da-Yan, ZHANG Bao-Guo, WANG Xi-Ming
1986, 10(5): 583-591.
Abstract:
Some experimental results measured for light emission particles with Z≤2 from 12C+64Ni reaction at E(12C)=69, 56MeV are reported. A comparison between moving source model calculation and proton's spectra have been performed. Extracted parameters of the source with faster velocity are agreement with the systematic values found before. The composite particle energy spectra of α, 3He and D were analyzed by coalescence model.
SINGLET DEUTERON INTERMEDIATE STATE IN d-d FOUR-BODY BREAKUP REACTION (Ⅱ)
ZHANG Ying-Ji, LIU Gen-Bao, ZHOU Shan-Zhu
1986, 10(5): 592-596.
Abstract:
At C.M. angles 90°and 64°two-dimensional spectra of protons emitted from singlet deuterons were measured under such geometry where the kinematic ambiguty was small. From the data it is obtained that the breakup energy EB of the singlet deuteron state is (52+21)keV.
FISSION EXCITATION FUNCTION IN INTERATIONS OF 12C IONS WITH VARIOUS TARGETS
LIU Guo-Xing, CHEN Ke-Liang, MA Hong-Fan, WANG Su-Fang, CAI Wei
1986, 10(5): 597-604.
Abstract:
Angular distributions of fission fragment and fission excitations was measured for a series of reactions 12C+169Tm, 175Lu, 181Ta, W, Re, Pt, 197Au, Pb and 209Bi in the 57.073.0MeV energy region with mica detectors and gold surface barrier silicon detectors. The experimental values <Γfn> we are abtained from fission excitation functions and compared to theoretical ones. The variation of the experimental values for the fission barrier height with the mass number A of the compound nuclei was studied and compared to the theoretical predictions by the liquid drop medel.
AN UNIFIED DESCRIPTION OF THE α-CLUSTERING AND COLLECTIVE EXCITATIONS IN HEAVY EVEN-EVEN NUCLEI
WU Hua-Chuan
1986, 10(5): 605-612.
Abstract:
In this paper, an algebraic model, U(6)×U(11), is proposed for an unified description of the quadrupole-collective motion, the α-clustering and the octupole vibration. The model's three dynamical symmetries: SU(5), SU(3) and SO(6) are given. The spe ctrum of the SU(5) limit is calculated and compared with the experimental data of the nucleus 218Ra.
THE IBM EXPRESSIONS OF B(E2) FOR INTER REPRESENTATION TRASITIONS IN DEFORMED NUCLEI
LING Yin-Sheng, GAO Shun-Fu
1986, 10(5): 613-619.
Abstract:
The general one body E2 operator is used to derive the analytic expressions of B(E2) from the first β and γ bands to the ground band under the SU(3) basis.
SHAPING AND ADJUSTING THE FRINGING FIELD OF IRON-FREE COILS BY USE OF SEPARATED COILS
LI Zeng-Hai, MAO Nai-Feng, SUN Qin-Ren
1986, 10(5): 620-628.
Abstract:
Magnetic field distribution, expressed in terms of coil parameters (geometric and current), of various kind of ironfree current wire elements is derived. A method for shaping and adjusting fringing field profile by the use of separated current wires which have different coil parameters is suggested, and the optimization of coil parameters is realized by the use of the method of least square. As an example, magnetic field profile of an iron-free magnetic β-ray spectrometer is shaped and adjusted to illustrate the use of this method.
CALCULATION OF THE ELECTRIC FIELD OF A MULTIWIRE DRIFT CHAMBER
XU Rong-Sheng
1986, 10(5): 629-631.
Abstract:

The matrix cap acity method used for the calculation of the electric field and the choice of the optimum voltages of the wires of the drift chamber used on the Beijing spectro-meter (BES) is described.

AN APPROACH TO THE STRUCTURE FUNCTION FOR UNCLEON
LONG Ming
1986, 10(5): 632-635.
Abstract:
The structure function for nucleon is discussed by using the method given in a previous paper. The formula are compared with the experimental data from low Q2 to high Q2. The results show that the way that the structure function for nucleon can be obtained from the hadronic wavefunction is a possible approach of investigating structure functions for hadron.
A DEDUCTION ON PRIMARY COSMIC PAY COMPOSITION AND SPECTRA ABOVE 1014eV
JING Cai-Liu, DING Lin-Kai, ZHU QiNG-Qi, JING Gui-Ru
1986, 10(5): 636-640.
Abstract:
The spectra of primary cosmic ray nuclei are fitted from experimental data under 1014eV and extrapolated to their bending energies. The primary cosmic ray composition above 1014eV is deduced according to the rigidity cut off model by selecting an appropriate bending energy for proton so that the sum of various nucleus components is consistent with the experimental total particle spectrum. The method used is independent on the behaviour of hadronic interaction.