## 1989 Vol. 13, No. S4

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**Abstract:**

In this paper the gas gain of a proportional tube is discussed. On the basis of analysing the existing calculation formulas, a new

*α/p*-

*E/p*relation and a corresponding formula of gas gain are proposed. The theory is compared with the experimental data of BF

_{3}and CH

_{4}proportional tubes.

**Abstract:**

Multiplicity distributions and pseudo-rapidity distributions of charged particles from oxygen-induced nuclear reactions at 14.6 and 60 GeV/nucleon are presented. The data were taken from the EMU-01 emulsion stacks and compared to simulations from the Lund Monte Carlo Model (FRITIOF).

**Abstract:**

On the basis of a simple grain boundary model, the trapped states of positrons at grain boundaries in pure Aluminum are solved and the corresponding lifetime spectra of positron annihilation calculated. The correlations between the atomic density distributions of grain boundaries and the lifetime spectra are discussed, and the existent experimental results are explained theoretically.

**Abstract:**

A part of K4 (1984-1985) Fe emulsion chambers exposed at Mt Kanbala (altitude 5500 m, atmospheric depth 520 g/cm

^{2}) by China-Japan Emulsion Chamber Collaboration has been analyzed with systematic scanning and measurement The distribution of the starting depths of the observed showers is given. The zenith angle distribution, vertical intensity, energy spectrum and attenuation length of hadrons in air and in iron are presented. Our results are compared with the recent data given by other experiments, and they are approximately consistent with each other.

**Abstract:**

By measuring the background darkness

*D*

_{B}of each yeai's (K0-K7) X-ray films, this paper presents the correlations between

*D*

_{B}and energy calibration value

*D*

_{1}. Several distributions of X-ray film's

*D*

_{B}are measured. The measured results can be used as the useful parameters for energy calibration and emulsion chamber experiments.

**Abstract:**

Cumulant expansion is used to calculate the mean plaquette internal energy for the d-dimensional SU(3) gauge theory. We use the methods of series expansion and steepest descent to calculate the SU(3) one-link invariant group integral. These two methods agree accurately with each other. The results show that the cumulant expansion is effective for 3-dimensional lattice gauge theory.

**Abstract:**

A new Hamiltonian in the massive lattice Schwinger model is proposed and the exajet ground state found. The string tension of the infinite string is exactly calculated in both the Naive and Susskind fermion schemes. The result shows that in both massless and massive lattice Schwinger models the string tension is equal to 1/2

*e*

^{2}. This indicates that as in the massless Schwinger model, one can obtain the linear confinement potential in the massive Schwinger model and no deconfinement phase transition occurs when

*a*approaches to 0. This result is in accord with that obtained in the continuum theory.

**Abstract:**

In this paper we discuss the production and decay of the glueball candidate

*θ*/f

_{2}(1720) in the J/ψ radiation decay. We find that in order to explain the ratios

*x*and

*y*of the helicity amplitudes of the process J/ψ→γ+

*θ*the contribution from two

*D*-wave components (

*l*=2,

*s*=0,2) must be considered in addition to the

*S*-wave component We also discuss the possible experimental test for the second

*D*-wave component (

*l*=2,

*s*=2).

**Abstract:**

The β function behavior for the

*O*(3)

*σ*amodel on the 2-dimensional random triangle lattice has been studied with the improved Monte Carlo renormalization group method. It agrees with the one calculated in the weak coupling region under two-loop approximation. However, when

*g*≥ 0.8, it drops down faster due to the higher-order perturbative and nonperturbative contributions.

**Abstract:**

The temperature dependence of

*σ*

_{vac}describing the extent of gluon condensation and of color-dielectric constant

*K*

_{vac}describing the confinement of quarks are discussed in the framework of nontopological soliton model at finite temperature. The mechanism of deconfinement transition is analysed.

**Abstract:**

A quark model calculation for the short-range contribution in the pion double-charge-exchange (DCX) reaction is presented. In the framework of this new model, the angular distributions of

^{18}O(π

^{+}, π

^{-})

^{18}Ne(g.s.) at low energies are calculated and compared with the experimental data. It shows that this model can explain the "anomalous" increasing behavior for the DCX reaction around 50 MeV quite well.

**Abstract:**

The differential cross sections have been measured for the

^{89}Y(

*α*,p)

^{92}Zr reaction with

^{92}Zr at the ground state and some low-lying excited states and for the

^{89}Y(

*α*,

*α*)

^{89}Y elastic scattering by using a 26.1 MeV beam. Fully microscopic DWBA analyses for

^{89}Y(

*α*,p)

^{92}Zr have been performed by using

^{89}Y and

^{89}Y shell-model wave functions with or without the core-excited conflguration. With the core-excited configuration, relative strengths of the ground state and the first excited state are greatly improved. Finally, the absolute cross section for

^{89}Y(

*α*,p)

^{92}Zr and the importance of the shallow well depth of

*α*optical potential are discussed.

**Abstract:**

On the premise of considering the Pauli exclusion principle strictly, we have obtained an exact general formula of multi-particle and multi-hole state densities for any singleparticle Hamiltonian. Besides, by using the semi-classical Thomas-Fermi approximation, we have-calculated the state densities for three-dimensional linear oscillators and the state densities of 1

*p*-10

*p*,1

*h*-7

*h*and 1

*p*1

*h*-6

*p*6

*h*. We have also discussed the effect of the Pauli exclusion principle and made comparisons with the state densities of the equi-interval model generally used in the exciton model. The results indicate that the equi-interval single-particle density formula is a good approximation for the nuclear reactions induced by a nucleon.

**ISSN** 1674-1137 **CN** 11-5641/O4

Original research articles, Ietters and reviews Covering theory and experiments in the fieids of

- Particle physics
- Nuclear physics
- Particle and nuclear astrophysics
- Cosmology

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