1989 Vol. 13, No. 11
Display Method: |
A part of K4(1984—1985) Fe emulsion chambers exposed at Mt.Kanbala (5500m,atmospheric depth 520g/cm2)by China-Japan Emulsion Chamber Collaboration has been analyzed with systematic scanning and measurement.The distribution of the starting of the starting point 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 consistent with each other approximately.
The DB-D1 relations are presented in this paper by measuring background darkness of the X-ray films in No.K0—K7 chambers,in addition,different distributions of the background darkness of X-ray films are measured.They may be taken as somemuseful parameters in energy calibration and other respects for future EC experiments.
The design and construction details of the barrel shower counter for BES are discussed.The barrel shower counter is cylinderical,of 2.5m inner diameter,3.4m outer diameter and 3.85m length,constructed on an aluminum spool of 2.5m diameter,3 cm thickness and 4.23m length.There are 23 layers of lead (0.5r.l. as an absorber) and 24 layers of selfquenching streamer (SQS) tubes.The total weight of the counter is 40,000kg and 80% of 4π sr soild angle coverage.
Ideal first-order phase transition and non-ideal phase transition that have supercooling quark phase in the early universe are analysed.The phase transition time in the two scenario are given.
We present a cosmological solution of eight-dimensional Kaluza-Klein theory with Georgi's three-family SU(11) model in M4,to which a matter term is added.In this solution,the general behavior of the scale factors is depicted in for stages.In stage one,both R3 and R4 expand with time;in stage two,R4 is a constant while R4 is a constant while R3 is an inflationary solution and R3 is an inflationary solution and R3 will continue to increase with time monotonically while R4 recollapses toward its minimum in stage three; finally,in stage four,R4 will be stabilized at RKK through some quantum effects and R3 expands with time in the usual FRW way in which the four-dimensional cosmological constant becomes zero.
In this paper the stress-energy tensors of curvature and of torsion are introduced.We may derived a model of strong gravity from Einstein's equation with the stress-energy tensor of torsion,while Einstein's equation with the stressenergy tensor of curvature is an inconsistent equation.This conclusion is different from the Poincare gauge theories of gravitation,in which the curvature is directly proportional to the strong coupling.
In this paper we discuss the production and decay of the glueball candidate θ/f2(1720) in the J/ψ radiative decay.We find that in order to explain the helicity amplitude ratios x and y of the process J/ψ→γ+θ,the contribution of two D wave components (l=2,S=0,2) has to be considered in addition to the S wave component.We also discuss the possible experimental test for the existence of the D′wave component (l=2,S=2).
The temperatrure dependence of the σvac describing the extent of gluon condensation,and that of the color-dieletric constant Kvac describing the confinement of quarks,are discussed in nontopological soliton model at finite temperature; The mechanism of deconfinement transition is analysed.
In this paper,an adequate form of qq Bethe-Salpeter (B-S) equation with one gluon exchange interaction and harmonic oscillator confining potential being taken into account has been derived,based on correct Gordon decompositions of the γ-matrices and a proper treatment for the fermion propagators in the equation.Furthermore,a Pauli-Schrodinger (P-S) equation including relativistic corrections has been established on the basis of the B-S equation by making use of relations between 4×1 components of the 16×1 B-S amplitude and a connection between the B-S amplitude and the P-S wave function both of which were found in the approximation of the order of p2/m2.Calculations of meson spectra by employing the latter equation give a better agreement with the experimental data.
The Eta-24Mg mesic mucleus and the Eta-32S mesic nucleus are considered as the 12C-Eta-12C and 16O-Eta-16O three body systems respectively.With the separable potentials which include only S-wave Eta-12C and Eta-13O interadtions as the effective interactions,the Schrodinger equa tions of the systems are solved in the Born-Oppenheimer approximation.The two-center problems are solved exactly first,and then the binding-energies of Eta-24Mg and Eta-32S are calculated.The calculated results are satisfactory.
The four-dimensional Langevin equation for two collective coordinates (the distance bet ween the centers of mass of the dascent fragments and the neck parameter) and their conjugate momenta is used as a dynamical equation to describe the descent of Brownian particles from the saddle-point to the scission points Monte-carlo method is used to slove the Langevin equation.The variances of the kinetic-energy distributions of nuclear fission-fragments in the range 32
Based on the model of nucleon exchange,including the nucleon exchange between two nuclei and the particle-hole excitation in a nucleus,this paper discuss the role of the dynamical evolution in nuclear deformation and the shell effects on the nucleon exchange process in dissipative heavy-ion collision.A nice agreement between theoretical results and experimental data has been gotten.
The emission rate of complex particle and problem of initial value induced by complex projectile in memory particle model are discussed,the mechanism of m-r cooperation emission is proposed.The fit of the calculation results with experimental data is good.
The differential cross sections have been measured for the 89Y(α,p) 92Zr reaction with some low-lying states and for the 89Y(α,α)89Y elastic scattering by using 26.1MeV α beam.A fully microscopic DWBA analysis for 89Y(α,p) 92Zr have been performed by using 89Y and 92Zr shell-model wavefunction with or without the core excited configuration.With the core excited configuration,relative strengths of the ground state and the first excited state are greatly improved.Finally,the absolute cross sections for 89Y(α,p) 92Zr and importance of shallow well depth of α potential are discussed.
- A SCOAP3 participating journal - free Open Access publication for qualifying articles
- Average 24 days to first decision
- Fast-track publication for selected articles
- Subscriptions at over 3000 institutions worldwide
- Free English editing on all accepted articles
- The 2019 National Day closure
- Editor Recruitment
- CPC authorship won the âIOP Publishing awards top cited Chinese authorsâ
- The 2019 summer holiday-Office closure
- 2018 Impact Factor 5.861