1982 Vol. 6, No. 4
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We solve, in this paper, the Bethe-Salpeter equation with spin (0-1/2) and unequalmass for Coulombic atom. The approximate solution thus obtained as well as theperturbation expansion of composite particle field theory are then applied for cal-culating the probability of production of (π士μ干) atom in KLo-decay. The comparisonwith a preliminary experimental result is also presented.
In this paper, the disintegration energy spectrum and Cross sections of the highenergy (π±μ干) and (K±μ干) atoms in screened. conlomb field are calculated usingperturbation expansion of the quantized composite field theory and relativistic B. S.wave functions of (π±μ干) and (K±μ干) In the extrarelativistic approximation,for a majority of atomic nucleus the disintegration Cross-sections of (π±μ干) and (K±μ干) are about 10-15 cm2 and 10-17 cm2 respectively. Furthermore, using the same B.S. wave functions above, the decay rate of(π±μ干)→π0+vμ(vμ); K±μ干)→K0+vμ(vμ) and π±μ干)→μ++μ-+vμ(vμ(K±μ干)→μ++μ-+vμ(vμ) are calculated.
In this paper we discuss a possible dynamical supersymmetry in complex nuclearspectra--the U（6/4） supersymmetry. The wave functions of these nuclei which contain several s d bosons and 0, 1, 2, 3,or 4 j=3/2, fermions, can be classified by a Lie superalgebra chain U(6/4)SU(6/4)SU(6)SU(4)SU(4)SU(4) SU(4)Sp(4)SO(3) and can be written as|λ+δ[σσ][14-δ][f] (λμ) △IM>, δ=0, 1, 2, 3, 4.where [σσ][14-δ],[f] are the lebels of the irreducible representations of each SU(4);(λμ) are the lebels of the irreducibele representations of Sp(4). All the permissiblevalues of [f] (λμ) △ I are calculated and a closed expression for energies is derived.
In this paper. the partial width of meson decay is calculated using the composite fieldtheory and the B-S wave functions corresponding to the harmonic oscillator model of meson.Preliminary results show that the theoretical calculation may be in accordance with experiment.
In this paper, using collective coordinate of A. Bohr. the Scattering amplitude oftwo complex systems is given. Collective excitation for two complex systems in thescattering process are discussed.
We have derived a modified expression for the QCD effective coupling constant totwo-loop order It amounts to adding the terms of higher order than Int/t which areindependent of the renormalization scheme to the usual expression. On the basis of theresult we proposed a in momentum and coordinate representation respectively, singleheavy quark potential which has the properties of both asymptotic freedom and as-sumed linear confinement, and obtained the slope of the linear potential at large dis-tances k=4π∧2/(33--2Nf). We bound that it is possible to determine the potential bymeans of the single parameter ∧ if the quark flavor number Nf is specified in abvance.
The potential advantages of RFQ Linas in the acceleration of low-beta particlesare commented. The r.f. electric field distributions and the equation of motion ofthe particles near axis in RFQ Linac are given. The beam capture efficiency and dis-tribution in longitudinal phase spaces as the function of RFQ parameters and injectionenergy are described. The preliminary design study of 750 keV proton RFQ ispresented.
The formulae of calculating the slop and the radius of the ion beam in the A2exit hole and the distance d2 between the two accelerting electrodes is drived basedon the theory of patallel axis linear optics. The influence of the uniform acceleratingelectric field and the space charge in the A1--A2 region on the particle trajectory isconsidered. An example is calculated numericaly and compared with analytic results.
The influence of the gliuon distribution in proton on the Compton effect in γ-pcollisions is discussed using perturbative QCD. Computing results show that the Comptoneffect is not sensitive to the power variation of the gluon distribution function, Onecan use the appropriate form for gluon distribution function to estimate the crosssections.
In the study of the dynamic process (for example, the deep inelastic scatteringof heavy ion, the nuclear fission), the viscosity which describes the coupling between theintrinsic degrees of freedom and the collective one is a basic quantity. In this paper,under BCS approximation we derive microscopic expression of viscosity coefficientwith pairing interaction by means of the linear response theory. Taking the fissionprocess of 236U as an example, we discuss the effect of pairing interaction on theviscosity coefficient. The results show that the pairing interaction must be taken intoaccount at the lower temperature and can be neglected at high temperature region.
Based on the s. d IBM proposed by Arima and Iachello, g boson is introducedTwo chains of subgroups, SU(15)SU(5)SO(5)SO(3) and SU(15)SU(14)SO(5)S0(3) (i,e two limiting cases, SU(5) and SU(14)), of the s.d.g IBM arediscussed. It is shown that there appear 1+ states in these limiting cases, but not inthe s.d IBM and s.g IBM. The spectra of 200Hg are calculated in the SU(14) and SU(5) limiting cases and agreed with experiments. The results show that the excita-tion of g boson is possible in some vibrational nuclei.
Atomic number and masses have been identified for target-like fragments producedin bombardment of 56Fe target with 790MeV 136Xe ions. Four neutron rich isotopes54Ti,56V, 57V and 58Cr have been detected and identified. Tentative identification for55Ti,58V, 59Cr is also presented. Using GSI magnet spectrometer, the isotope identifica-tion combined magnetie analysis as well as time of flight and △E-E measurement wasquite unambiguous.
Assuming fission fragments are in statistical equilibrium state at scission point,we can consider the particle number distributions of fission fragments as the fluctua-tions around some average values. and treat them by means of quasi-thermodynamicmethod. The main result is that all distributions of mass number, charge number,isotopes and elements are Gaussian distributions around some average values andwith constant variances, and that all relevant parameters depend on temperature andproperties of fragments near the most probable fission mode only. We have determinedthe values of five fundamental parameters for the case of 235U(11th, f) according tothe experimental data, and use them to calculate the other parameters. The agree-ment between theory and experiment is satisfactory.
With a usual choice of the effective nucleon-nucleon interactions consisting of apairing force, a quadrupole pairing force and a quadrupole-quadrupole force, the mic-roscopic approach, as dascribed in our previous work based on the Dyson bosonexpansion and based on the so-called modified Jancovici-Schiff substitution is fol-lowed to obtain a group of eigen-equations for determining the IBM bosons and findthe microscopic expressions of the coefficients appearing in the interaction terms ofthe IBM Hamiltonian. The results given in the present paper can be used directly incalculating the collective spectrum of nuclei with identical valence nucleons outsideclosed shells.
Using the eigenvalue equation derived from the single particle (sp) Green's func-tion and the reaction (G) matrix based on the Hamada-Johnston potential, we havecalculated the sp energies of 17O and the sh (hole) energies of 15O as well as therelative magnitude of the corresponding transfer matrix elements. As a first step,we have only considered an approximation for the mass operator up to the first-orderin G, however the energy dependence of G has been taken into account properly. Theeigenvalue equation is solved by a self-consistent procedure (SCP). We have speci-fically investigated the rate of convergence of this SCP and that of the truncation ap-proximation. Further, the effect of the spurious center of mass motion and the depen-dence of our results on the input values of parameters of the harmonic oscillatorpotential which is used as the initial approximation of our SCP have also been studied.The calcuated results fit the experimental values quite well, though the method used ismuch simpler than the renormalized Brueckner-Hartree-Fock method.
In order to investigate the poss ibility of the existence of the ultradense nuclei, wehave used a lead glass Cerenkov total absorption spectrometer to search for highenergy γ rays in the spontaneous fissions of 252Cf. It follows that the upper limit ofthe probability of γ rays in the energy range between 50 and 240 MeV is 1.4 ×10-6/fission (95% confidence level).
A method of synchronous transfer of beam from the booster to the main ring isproposed. In order to meet the character of the BPS, the ratio of the radii is notstrictly equal to the harmonic ratio between two machines. The physical picture andthe choice of parameters in this method are discussed.
A method using coils to measure effective length of pulsed quadrupole lense isdescribed. This method is fast in picking up signals and simple in data processing.The coupling coils are made of printed circuit.
We estimate and measure the sensitive time (≈ 1.82 μs), recovery time (20 ms)and repetition time (0.25s). of the parallal plate optical spark chamber. The variousfactors that influence sensitive time are discussed. The ordinary methods to reducesensitive time are dascribed.
In this paper reduction of the beam energy spread of RFQ for nuclear physics bydebuncher is discussed. The equation of the curve of the beam energy spread afterdebuncher effect is presented. The choice and the calculation of the debuncher parame-ters are also described.
CR-39 is a good material of solid state track detectors. In this paper theresults of some behaviour tests are described.
In this paper we have calculated differences of the binding energy between A3He and A3Husing the ∧-N meson exchange potential , And lov excitation energies of A3H. The resultsare reasonable in comparison with the data.
In this experiment we setrched for relativistic particles with mall charge in cosmicrays by a coincident NaI(TI) counter telescope, In the telescope both NaI (TI) countersare used to measure the ionization loss of the particles in order to determine the chargeof the relativistic particles. An annular anticoinicident counter is used to reject thebackgrounds from the sides. The experimentally measured charge range is from 1/12to 1/4 electron charge The preliminary measurements give the follewing upper limitsof flux of particles with small charge in cosmic rays on the sea level, which are notwithin the core of the air shower,less than 4×10-5 particles/.cm2 ·sr·sec in the 0.08 to0.19 electron charge range and less than 2×1O-5 particles/cm2·sr·sec in the 0.19 to 0.25electron charge range.
We have made a comparison of the single particle (sp) and single hole (sh)energies in the 16O region calculated by the Hamada-Johnston, the soft Reid and theParis potentials. It seems that the Paris potential gives a better result than the othertwo.
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