1986 Vol. 10, No. 4
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The Monte Carlo method based on the functionization of the performance of defectors and the transformation of values of kinematical variables into"measured" ones by means of smearing has been used to program the Monte Carlo simulation of the performance of the Beijing Spectrometer (BES) in FORTRAN language named BESMC. It can be used to investigate the multiplicity, the particle type, and the distribution of four-momentum of the final states of electron-positron collision, and also the response of the BES to these final states. Thus, it provides a measure to examine whether the overall design of the BES is reasonable, and to decide of the physical topics of the BES.
A cosmic ray super high energy family event with visible energy of about 1500TeV and five big cores is reported. This event was found in the 1980—1981 exposure of Mt. Kambala(5500M a.s.l.) emulsion chamber experiment. The family characteristics are analized and compared with the other cosmic ray events in the same energy range. The production and fragmentation characteristics of the five jets are studied and compared with the experimntal results of accelerators and C-jets as well as with QCD predictions up to TeV. Some features on hadronic interactions at TeV range are disccused.
The recent results from Mark J on two photon muon pair production with √S from 14 to 46.78GeV are presented, and compared with the complete α4 QED calculation in a large range of √S and four momentum transfer, including untagged, single and double tagged events. The forward-backward charge asymmetry of muons produced in the two photon process in also compared to the QED prediction.
Charged boson bound states in Kerr-Newman metric are discussed. It is found that massless boson cannot be attracted by Kerr-Newman black hole to form bound states. For the massive boson, the condition of the nonbound states when 0<α<√M2－Q2 and both the condition ane wave functions of the bound states when a=√M2－Q2 are obtained. The energy mode of the bound states is single, E=(√M2－Q2+eQM)/(2M2－Q2). When Q=0 or e=0, the conclusion is in agreement with that of Zhang Shi-Wei and SU Ru-Keng.
A composite model with hypercolor group being semi-simple gauge group is discussed. A SU(4)×SU(4) composite model with confining weak interactions is proposed, which gives three families of light fermions.
The curve of KNO scaling and the multiplicity moments in pp collsion √S=540GeV are calculated by independently-produced-many-fire ball model. Comparison with exper iments shows a good agreement between the data and theory. The physical back ground the model is analysed.
Rieman-Hilbert transformation is applied to the four-dimension Anti-Self-Dual equation and 'tHooft's instanton solution is derived.
The influence of EMC effect on Drell-Yan processes at high energies of hadron-nuclei collisions is discussed. After adapting the Jaffe's rescaling formula which express the EMC effect on deep inelastic scattering off nuclei and making use of the parton dlstribution function fitted by Duke and Owens, D-Y cross sections of various nuclei is calculated, which can be compared with experimental data, and it is found that the EMC effect affects these processes very little. After taking into account the disagreement between the data of EMC group and SLAC group at x<0.25, considerable change was found but yet the data of the dependence of cross sections on the nuclei can not be interpreted satisfactorily. It is suggested that the D-Y processes of h-A collisions at those kinematic region where the EMC effect has notable influence should be measured.
The influence of the meson radial structure on the meson-baryon vertex functions is studied. A mixing wave function of 0S state and 1S state is used to compare with the 0S structure calculation. The result shows that the mixing structure is important for improving the coupling constant of NNπ vertex.
Analytical expressions of two kinds of permanent magnetic steering magnets are derived. Comparisons with conventional steering magnet are given.
The defects in GaAs grown with the melt growth method at 1238℃ and with the Te-doped LPE method in the temperature range 750—950℃ are studied by positron annihilation. The lifetime component τ2 exhibits a constant value of 312±11ps in the temperature range 800—1238℃. The intensity I2 increases with the growth temperature. In the Te-doped LPE crystals, the concentration of the positron trap increases linearly with temperature. The trap is considered as Ga vacancy. The results show that doped Te in GaAs induces Ga vacancy.
The β-Spectrum of 100Sr produced by ISOL facility TRISTAN is measured by a ΔE-E telescope detector system, whose response function is calibrated by means of a monoenergitic electron beam. The β－ strength function of the 100Sr decay is then extracted from the β-Spectrum directly. Based on the schematic B-B model, the β－ strength function for the allowed GT transition of 100Sr decay is calculated. The consistence between the experimental and the theoretical results is fairly good.
The ion optical characteristics of 32 magnetic quadrupole multiplet microbeam-forming systems with different configurations and excitation modes are calculated and analysed by the of matrix and ray-tracing methods.
In this paper the s.d.g. IBM is used to calculate the energy spectra of the light nuclei 44,46,48Ti, and the results are compared with the calculations based on the pure configuration shell model, and with the experimental spectra.
Laser-stimulated enhancement of p-wave radiative capture of low energy neutron is studied, with aiming at investigations of p-wave neutron resonance near neutron binding energy, which can not be observed in the usual low energy neutron induced reactions. The cross sections for such processes are calculated in second order perturbation theory and expressed in term of the intensity of laser radiation and the nuclear matrix elements. Numerical estimates show that an appreciable enhancement of the radiative capture will not be observed until the laser electric field strength reaches a magnitude of 105 to 108 (V/cm), depending whether an s-wave resonance exists simultaneously in the entrance channel.
The geometric parameter optimization of high field magnets is studied in this paper by using both magnetic circuit calculation and magnetic field calculation. A model magnet of 31kG in magnetic induction was made. The magnetic field measurements are in good agreement with the calculations.
In order to avoid the inconvenient resulting from the non-linear phenomenon in realization of isochrone magnetic field, the efficiency function of trim coils in SSC2 at GANIL is obtained by means of exploiting the results of magnetic field measured.
By using the valon model, the electric form factor of the proton in the nucleus GEP(Q2), and π decay constant fπ are discussed. After combining the (e,e') reaction on the 56Fe near the quasielestic peak, it is found that GEP(Q2) and fπ are influnced by the nuclear medium and their modifications result from increased hadron size as the distortions of structure functions (EMC effect) do.
B.W.Lee's equation Γ*Γ=0 is generalized to a new equation ΓAF*ΓAF=0 after letting dλ=ζ1ζ2ζ0. It is found that the condition that quadratic change of B.W.Lee's form is zero makes no restriction to such a generalization. The derived formula not only contains B.W.Lee's one, but also can be used to solve ather questions.
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