1980 Vol. 4, No. 5
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It is shown that there exist connections in some of the present gauge theories andthe theory which can provide a mass to the gauge particle without the usual sponta-neous symmetry breaking.
By using the distribution functions of the valence stratons with definite helici-ties, the differential cross sections and asymmetries of 1. the deep inelastic scatteringprocesses of electrons on polarized protons, polarized neutrons and polarized nucleons,and 2. the process p+N→μ+μ-+X (where the p and N are polarized) are comput-ed. From the kinematics, it is shown that no polarization effects exist in the process π(K) +N→μ+μ- + X (where N is polarized). Also from the parton model it isshown that no polarized effects exist in the process P + N→μ+μ- + X (where P and N are polarized).
In this paper we have described a computational method of high intensity beamtransport systems. This is a step by step approximation method. In addition, wehave developed the general formulas for the calculation of systems including arbitrarynumber of bunchers.
The winding number is calculated from the instanton solution under differentgauge conditions. It is observed that, though the boundary condition is definite, thevalue of the winding number still depends on the way of approaching infinity. InLandau gauge, it leads to winding number of half integral value by the limiting waywith clear Physical meaning. Particularly in temporal gauge and the result is irre-levant with the limiting way.
Using Migdal's theoretical results of "pion Condensation", the influence of "π condensation" on the distribution of charge of N=Z nucleus is determined. The elastic-scattering differential cross-section of energetic electron by 40Ca nucleus is also calculated. The results of our calculations agree better with the experimental data.
Assuming that the atomic nuclei are bounded by a scalar meson field, their averageproperties were calculated by Thomas-Fermi method and Van der Waals approximation.Taking the mass of the scalar meson to be 472MeV and the radius of the repulsive coreof nucleons to be 0.57fm, the calculated expresion of binding energies is similar to theempirical formulae. Nucleus with N>Z has a neutron skin.
Nonlinear space-charge effects of low energy intense charged particle beams arestudied by analytical method. The relation between changes of emittance diagramsand initial current density distributions for zero temperature beams is deter-mined. Approximate methods for calculating changes of emittance diagrams for beamsof small temperature under the action of nonlinear space-charge field and increment ofeffective emittance of beams are obtained.
In this paper, we analyse the commutation relations of the infinitesimal generatorsof all simple classical Lie groups and establish a new basis for these generators, calledthe tensor basis. In tensor basis, the infinitesimal, generators can be written as somescalar operators, some sets of angular momentum operators and some sets of irreducibletensor operators. The commutation relations, of these operators are very simple andhave many regularities. By means of the method that has been used in the earlier papers, "On the irre-ducible representations of the compact simple Lie groups of rank 2, I,II,III" and thetensor basis, all the irreducible representations of the classical simple Lie groups canbe calculated systematically.
We point out the possible existence of bosonic charged partons (diquarks) withinnucleons. A certain form of the structure functions of diquarks inside nucleons is as-sumed and the functions are suitably parametrized. Then, by combining their effectswith the usual QCD calculations, we get a better theoretical fit to the experimental R=(σL)/(σT) value in e-p deep inelastic scattering.
In this paper a unified electro-weak model for leptons based on the SU(3) gaugegroup is suggested by means of four kinds of realization for the generators of thegroup. For all low energy electro-weak processes, this model predicts the same resultsas the conventional Weinberg-Salam model does. The Weinberg angle is shown to be sin2θw=1/4 in a natural way. When the Higgs self potential respects a discrete symme-try Φ→-Φ, a new conserved quantum number called weak strangeness emerges fromthe model after spontaneous symmetry breaking. In the present model there existanother four heavy vector gauge bosons V± and U±± together with some heavyfermions and Higgs scalars, which have non vanishing weak strangeness quantumnumbers. These weak strange particles have no direct couplings with leptons. Theirexistence will not influence the low energy electro-weak processes. Nevertheless, theycan be produced in pairs in high energy collisions and the lightest of them should bestable if the conservation of weak strangeness is exact. The experimental implicationsand the possibility of violation of the conservation of weak strangeness are also dis-cussed.
The asymptotic completeness is discussed by using optical theorem.
In this paper a three bands intersection model describing the high spin states ofeven-even nuclei have been proposed. This model has the ability to explain the back-bending behaviour in the plot of the moments of inertia versus the rotational angularvelocity, i.e. l-ω2 curve, of some even-even nuclei.
For the nuclear mass even-odd difference ratio P/P′, there is sharp contradictionbetween Danos-Gillet's mass formula and the experiment. A new formula is presentedin this article, which has the different forms of coulomb energy, symmetry energy andpairing energy terms from the convensional ones. Not only it gives right value of P/P′but also the good agreement of β stability position and calculated binding energy withthe experiment are obtained.
Based on the transport theory of nucleons of fission nucleus, we have calculatedthe mass distribution of U fission induced by thermal neutron using Fokker-planckequation and in the calculation, the kinetic energy distribution and other phy-sical quantities are also obtained. Our results agree semiquantitatively with existingexperiments.
An analysis and discussion has been made for the properties of the triple bandforking in Ge. We also give some supports and questions for the existing explana-tions.
The interaction of the rotational three-band, the superband, the g band and theβ band (or γ band), for even-even Nuclei is discussed. The Hamiltonian matrix is diagonalized after solving the secular equation bywhich the parameters in the matrix elemen s are determined. The three-band spectrafor more than ten nuclei have been calculated. The calculated results are found to bein resonable agreement with experimental data, and some informations of three-bandmixing are obtained.
This paper has explored the relations among the energy transfer and the linear andanglar momentum transfer in heavy ion reaction from the theoretical point of view.
On the basis of the straton model, we have considered the bound state of mesonsby using the Bethe-Salpeter equation. The result shows that by using the superposi-tion of the deep square well, the harmonic and Coulomb-type potential, we can qualita-tively explain the mass spectrum, the mean radius and the wave function at the originfor the bound state of mesons.
After simplifying the two types of Morpurgo's quark-antiquark interaction poten-tial, in the framework of SU(4) the three neutral mesons of 0-+, 1--, 1+-,2++, whose charges, strangeness and isospins are all null, are mixed. The mass spectrum for the quark-antiquark consitituents of the mixing mesonsare calculated and compared with experiments.
In this paper, by using the time dependent projection operater method, the coup-ling equations of the relative motion, in classical limit, collective osillations and singleparticle excitions have been derived. These theorelical formulations are expected to be useful for the descriptions of thetransport process for the inelastic collision between heavy ions as well as nuclear fission.
Mass and kinetic energy distribution of fragments in thermal-neutron in-duced fission of 235U are calculated by a α decay-like model. Besides Coulomb andnuclear interactions, the deformation and intrinsic excitation energies of fragments arealso taken into account.
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