1985 Vol. 9, No. 6
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In this paper the time variation associated with light transmission in large area scintillators is investigated. The time distribution of photons which reach the end of scintillator is given. The light transit velocity and efficiency is discussed in detail.
The characteristics of cosmic ray hadrons are studied by use of mountain emulsion chambers installed on Mt. Kambala 5500m above sea level. The power index of the differential energy spectrum is (2.98±0.49) in the energy region from 2TeV to 20TeV. The vertical flux of hadrons with Ehγ≥3TeV is =(400±50)/year﹒m2﹒sr, their attenuation length in air is (104±16)g/cm2, the mean interaction lengths of hadrons and mesons in Pb are (15.3±3.0)cm and (18.6±4.7)cm respectively, and the ratio of meson-to nucleon in cosmic ray hadrons on Mt. Kambala is (1.0±0.4).
The spherically symmetric monopole of SO(10) grand unification model is discussed. The Jackiw-Rebbi type fermion-monopole zero-energy bound states are also considered in this model. It is shown that there is no zero-energy bound state in this theory.
Two kinds of SU(3)sc×SU(N) composite models (the model A and model B) of quarks and leptons are suggested to solve the family problem. The constituents (preons) of the models are two types of massless spin-1/2 fermions which belong to (3,N) and (3, N*) representations of the gauged symmetry group SU(3)sc×SU(N). Applying the Fermi principle to three-preons supercolor-singlet composite fermions and according to the models' requires ments (the fermions in one family originates from the same representation of SU(N) and belong to the same representation of the horizontal gauge group), one obtains the family-number of SU(3)sc×SU(N), whereSU(3)sc×SU(6) and SU(3)sc×SU(5) of the model A predict three and five generations respectively.
We calculate the cross-section differences:
(a) dσ(pp→Jet大PT+γ大PT+X)-dσ(pp→Jet大PT+γ大PT+X)
(b) dσ(pp→2γ大PT+X)-dσ(pp→2γ大PT+X)
(c) dσ(K-p→Jet大PT+γ大PT+X)-dσ(K+p→Jet大PT+γ大PT+X)
(d) dσ(K-p→2γ大PT+X)-dσ(K+p→2γ大PT+X)
(e) dσ(pp→2Jet大PT+X)-dσ(pp→2Jet大PT+X)
and find that they are not affected by gluon and sea-quark distribution functions and various fragmentation functions. Comparing these results with the corresponding expe rimental data, one can accurately determine the ratio αs/α under the present experimental conditions.
An electro-weak unified model based on SU(3)×U(1) group is suggested, which is left-right symmetrical and assuming the same interactions of neutrinos (or antineutrinos) with charge leptons and antileptons before spontaneous symmetry breaking. It is anomaly free and sin2θw1/4 can be drived. The difference between the model and the Weinberg-Salam model is very small in the low energy range. The lepton number is generalized to the lepton charge. It is proved that only lepton charge is strictly conserved and the individual conservation of the lepton number of every generation of leptons hold only approximately. The quarks have not only baryon number and charge but also lepton charge. This model predicts processes μR→eR+νeL+νμR, e-+e-→μ-+μ-, etc.
The differences of physical properties between several time-displacement operators are analyzed systematically. By using the Feynman propagator, a new time-displacement operator is reasonably constructed, with which the Hermite potential of relativistic equaltime equation is derived. Consequently, this equation is turned into a relativistic Schrödinger equation, in which the Hamiltonian is a Hermitian differentio-integral operator. Furthermore, the equaltime potential of minimum electro-magnetic coupling in first order is calculated. When the mass ratio of one particle to the other tends to infinity, the equation reduces to Dirac equation naturally.
This paper discusses the behaviors of the photon structure function, which is considered as a superposition of a hadronic and a pointlike component. The pointlike component is calculated in the quark parton model. The hadronic part is calculated in the vector dominance model. The valence quark distribution function of ρ0 is assumed to be the same as that of π0. The π0 valence quark distribution function is represented by an analytic expression in the leading logarithm approximation from the Altarelli-Parisi equation. Results obtained are in agreement with experimental data.
The method of stochastic quantization is applied to the lattice gauge field theory and the Langevin equations for the link and Wilson loop variables are established for the U(N) and SU(N) cases. The relation between the Langevin equation and the Schwinger-Dyson equation for the Wilson loop is discussed.
In this paper, the differential cross sections of the inelastic scatterings of protons of energy ~1 GeV on 152Sm, 145Sm and 176Yb are calculated by the method of the collective coordinate and High Energy Cluster scattering theory, using axially symmetric rotational model and the optical model with a woods-saxon potential. The results are in agreement with experimental data.
The energy spectra and angular distributions induced by 7—5MeV/A 14N on 59Co and 51V are measured by using semiconductor detector. The atomic numbers and quantities of the contamination heavy element are determined. The angular distributions of the elastic scattering are fitted by using General Fresnel model. The possibility of extracting the quasi-elastic cross section from the fitting procedure is discussed.
The cross sections of deutron-deutron reaction for deutron energy from 15 keV to 150keV and of deutron-tritium reaction for deutron energy from 13.5 keV to 114.3 keV were measured by the process of passing a deutron and tritium beam into a gas target formed by a differential pumping system and two capillary pipes. Experiments in two steps-angular distribution measurement and absolute differential cross-section measurement-were performed at 3 Cockcroft-Walton generators with terminal voltages of 50 kV, 150 kV and 300 kV. Emperical fit of D-D reaction data to Gamow formulae and comparison of D-T reaction data with BWE theory were given.
Basing on the experimental 2+ levels and the behavior of the variations of the effective gap coming from the N~λn plot in gauge space, relations between proton and neutron subshells are pointed out.
The competition between proton and neutron shell effect and proton-neutron correlation are discussed too. As an example, Z=38, 40 and N=56 subshells in region of A≈80—100 are analyzed in detail.
By using the d-α cluster-structure wave function and the nucleon-nucleon (N-N) force containing a soft-repulsive core central potential and a spin-orbit noncentral potential, the (1+, 0) ground state, (3+, 0) 1st excited state, (2+, 0) 3rd excited state, and (1+, 0) 5th excited state of 6Li are studied by phase-shift analysis and generalized eigenvalue analysis with single-channel resonating group-method (RGM). The results show that, from the phase-shift and eigenvalue analyses, the ground state of 6Li is mainly an l=0 d-α cluster-structure bound state, and the 1st, 3rd, and 5th excited states of 6Li are mainly (1,J)=(2,3), (2,2), and (2,1) cluster-structure unbound states, respectively.
Taking into account of the effect of deformation and using the scission point equations and equal-temperature condition, the formula for estimating excitation energy of fragments in fusion-fission and quasi-fission induced by heavy-ions is obtaind in this paper. When the quadrupole deformation coefficients α1=α2=0, the equation returns to the well-known formula E1*/E2*=A1/A2.
The isotope distributions of products in DIC from 14N+58Ni and 14N+64Ni reactions at 93 MeV are obtained. A systematic difference of the distributions at the same angle for both reaction systems are found, the isotope distributions for latter reaction system drift towards neutron-enriched isotopes.
By assuming that the polarized parton distributions and the polarized parton fragmentation functions in a photon satisfy an inhomogenous evolution, their moments are obtained. Explicit expressions for these moments are introduced by using series expansion of Jacobian polynomials. The 3-term, 5-term and 7-term expressions are given.
The 9ΛBe hypernucleus is considered as a α+Λ+α three-body system. With a saparable potential which includes only s-wave Λ-α interaction as the Λ-α effective interaction, the Schrödinger equation of the system is solved in the Born-Oppenheimer approximation. The two-center problem is solved first, and then the binding energy of 9ΛBe ground state is calculated. The calculated result is in good agreement with the experimental value.
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