2π→2K SCATTERING AND πK ELASTIC SCATTERING

The 2π→2K low energy scattering cross-section was obtained using the relation between field and current. The low energy πK elastic scattering cross-section and its scattering length were also obtained using cross symmetry.     

THE DIFFICULTY OF THE DECAY τ→πντ AND SPIN 3/2 HEAVY LEPTON

We discuss the suppression of the decay of heavy lepton τ into πv_τ,by assuming that τ and/or v_τ carry spin 3/2. For the case of spin 3/2 T and spin 1/2 v_τ, using the weak current ψ_μ^(τ)(a+b_^γ5)Ψ^(v_τ)we find that the πv_τ decay channel relative to the v_τv_ll^-channel is suppressed 12/5 times, while other decay channels are not changed appreciably. △R=σ（e⁺e^-→τ⁺τ^-）/σ（e⁺e^-→μ⁺μ^-） is also discussed.     

ASYMPTOTIC FREEDOM AND THE WAVE FUNCTIONS AT THE ORIGIN AND THE ENERGY LEVELS OF THE J/ψ AND THEY

On the basis of phenomenological quantum chromodynamics (QCD), a nonre-lativistic linear and Coulomb-like potential describtion of the strong interaction be-tween quarks is assumed and it is considered that the effective quark-gluon coup-ling constant approaches the asymptotically free limit of QCD. The cloice of thepotential parameters is so made as to fit the experimental values of the wave func-tions at the origin as well as the masses of the J/ψ and the γ Following the calcu-lation referring to the ψ′and the γ′, we acquire a consistent explanation for boththe relative values of the wave functions at the origin and the experimental mass asdifferences of these particles.     

THE EFFECTS INDUCED BY A Λ HYPERON ON THE PAIRING CORRELATION IN NUCLEUS

In this paper, the effects induced by a Λ hyperon on the pairing correlation in nucleus are investigated. For simplicity, the δ-type A-N residual interaction is adopted. We have calculated the energy Spectrum and wave function of the low-lying excited states for _Λ¹⁰O. Then using infinite sum approximation, the correlation effect for two nucleons in the high energy shell induced by a Λ-hyperon is discussed.Finally. by means of Bose approximation, the correlation effects for n pairs of nucleons induced by a Λ is analysed.     

HADRONIC PRODUCTION OF J/ψ、ψ′(3684) AND THE CONTENT OF THE CHARMED STRATONS IN THE SEA OF THE STRATONS

Hadronic production of J/ψ、ψ′(3684) particles is discussed in this paper on thebasis of reference [1] after considering the massive effects of the charmed straton.The results of [1] are improved.With the aid of the decay of ψ″→DD and the effective coupling constant between ψ″(3772) and the charmed straton we estimate that the content of the charmed stratonin the sea of the stratons is 0.41% of the ordinary stratons at most.     

ON THE ANGULAR MOMENTUM DIFFERENCE i(ω) BETWEEN SUPER-BAND AND GROUND-BAND

Some discussion is made for the angular momentum difference i(ω) introduced byA. Bohr and B. Mottelson.     

THE RESONANCE OF THE CHAIN STRUCTURE STATES IN A(α,αx)B TYPE THREE-BODY REACTIONS

In this Paper a calculable three-body T matrix with compact kernel is obtained by using multiplier's methods. The formulations for calculating the A（a, ax）B type three-body reaction trans-tion amplitudes are presented when plane wave or distorted wave is used for the incident and outgoing states. This T matrix also includes the resonance terms of the three-body chain struc-ture states besides quasi-free scattering terms and final states interaction terms. A calculable formulation for the resonance energy of chain structure states is presented when it is expanded approximately into two two-body bound states. For ⁸Be and ⁶Li as target nuclei, the resonance energies are calculated. The results are in good agreement with the experimental values and the theoretical values of a mole-cule-like model. In order to check this kind of resonances, some experiments are proposed.     

The reaction pp→pΛK + near threshold

We analyze the recent total cross section data for pp→pΛK ⁺ near threshold measured at COSY. Using an effective range approximation for the on-shell pΛ S-wave final state interaction we extract from these data the combination ?= (2|K _s|²+|K _t|²)^−1/2= 0.38 fm⁴ of the singlet (K _s) and triplet (K _t) threshold transition amplitudes. We present an exploratory calculation of various (tree-level) vector and pseudoscalar meson exchange diagrams. Pointlike ω-exchange alone and the combined (ρ⁰,ω,K^*+)-exchange can explain the experimental value of ?. The pseudoscalar meson exchanges based on a SU(3) chiral Lagrangian turn out to be too large. However, when adding π⁰-exchange in combination with the resonant πN→S ₁₁(1650) →KΛ transition and introducing monopole form factors with a cut-off Λ_c= 1.5 GeV one is again able to reproduce the experimental value of ?. More exclusive measurements are necessary to reveal the details of the pp→pΛK ⁺ production mechanism. Received: 28 October 1998 / Revised version: 12 January 1999     

THE π CONDENSATION EFFECTS IN FINITE NUCLEI

In this paper the π condensation effects in finite nuclei are investigated. We have supposed a model hamiltonian, and have calculated the eigensolution in the Random Phase Approximation. The energies and the π condensed number of the graund state and the one phonon excited states are obtained. The results are discussed for the case of ¹⁶O.     

THE STUDY OF SOME NON-SOLATED RESONANCES FOR THE 23Na （p,α）20Ne REACTION

The excitation functions of the ²³Na（p,α₀）²⁰Ne_g·s.and the ²³Na（p,α₁）²⁰Ne_lst reae-tion have been measured from E_p=1 to 2.5 MeV at θ_L=30°,150° and 30°,respectively.Around the resonance at 2.171 MeV,the excitation functions of the（p,α₀）reactionhave been measured at 12 angles,then,some angular distributions have been obtained from these excitation functions.In addition,the angular distribution of the（p,α₀）reaction for the resonance at 2.171 MeV has also been measured directly at energy ofthe resonance peak of the excitation function at 150°.For the resonance at 2.117MeV,the angular distribution have been measured at two energies,one at the energyof the resonance peak of the excitation function at 150°,another at the energy of thehalf maximum point of the resonance peak on the higher energy side.Around the re-sonance at 2.075 MeV,the excitation functions have been measured at 16 angles,andthe angular distribution has been obtained from three excitation functions.The an-gular distributions of the three resonances are not symmetric about 90°,and the posi-tions of the resonance peaks of these resonances varies with the angle of measurement.By means of the compound nucleus theory,discussions have been made for these non-solated resonances.     

THE POTENTIAL WELL DEPTH OF Λ PARTICLE IN NUCLEAR MATTER DUE TO MESON EXCHANGE POTENTIAL

The potential well depth of Λ particle in nuclear metter is calculated by using the Λ-N potential from single K, η, ω and 2π, πρ meson exchanges.     

HEAVY LEPTON τ PRODUCED IN e+e- ANNIHILATION BY THE INTERFERENCE BETWEEN ELECTROMAGNETIC AND WEAK INTERACTIONS AND PARITY VIOLATION EFFECTS

We propose the precise measurement of energy spectra of cascade π and ρ inprocesses e⁺e^-→τ⁺τ^-→e⁺π^-（p^-,μ^-）+ neutrinos in order to determine parity-violatingeffects due to the interference between the electromagnetic and weak neutral currentinteractions.These observations are feasible especially at heavy narrow resonances.Empirically we conjecture that the next quarkonium may be at 28—31 GeV.     

QCD PREDICTION FOR THE REACTION γ+p→2γ+X

In the framework of the perturbative QCD, the two-fold differential cross section d²σ/dx_Tdx_L of the reaction γ+p→2γ+X and its two backgrounds (γ+p→γ++X, γ+p→γ++X) are calculated in c.m.s.. The results show that, in a large range of (x_T, x_L), the calculated reaction cross section can be measured in current laboratory condition. And due to the properties of this reaction, i.e., large p_T photoproduction and direct photon pair emission, all of the backgrounds can be greatly suppressed.

     

THE EFFECTIVE POTENTIAL BETWEEN QUARKS TO THE ORDER OF υ2/c2

We analyse the necessity and possibility of introducing an axial vector piece into the effective potential in order to cancel the spin-orbit interactions and the problems related thereby.

     

DETERMINATION OF LEPTON LIKE-CABIBBO ANGLES AND PROBABLE INTERPRETATION OF μ→eγ TYPE PROCESSES

Massive heutrino and neutrino mixing are assumed. We get an equation of themixing angles and the neutrino mass ratios by horizontal symmetry. The conerete values of mixing angles are calculated. They are not contradictory with experiments. Inorder to explain μ → eγ process, exchange of neutrino with mass of GeV order isassumed. This neutrino is probably just the neutrino of fourth generation.     

重子场流关系式和过程p+n→n+K+■

我们在前一篇文章中讨论了重子场流关系式,并以质子为例,计算了ppπ顶角,获得了与实验相符合的结果.本文应用重子场流关系式到p+p→pKA过程和p+n→nKA过程.目前实验上已观测到p+p→pKA过程,例如在实验室系入射质子的动能为2.85GeV时σ(pp→pKA)=0.0510mb.(1)本文企图利用重子场流关系式,由pp→pKA过程的实验结果获得pn→nKA过程的一些     

Deuteron fragmentationd+p→p+p+n at 9 GeV/c

Gamma-ray energy correlations have been measured for several reactions leading to light-mass Hf isotopes with 160 ?A?166. The correlation spectra show ridge-valley structures up to high rotational frequencies from which a drop in J _c ⁽²⁾ is deduced at high frequencies. This drop suggests that a large portion of the angular momentum is generated by aligning particles. It may also be explained by the theoretically predicted triaxial states with large deformation.     

THE DOUBLE SPECTRAL FUNCTIONS OF PHOTON-NUCLEON SCATTERING AND INELASTIC CROSS-SECTIONS OF γ+p→p+π++π-

Using elastic unitary condition of t channel, the double spectral function of photon-nucleon scattering and absorbtive parts of scattering amplitude (s channel) are given. Using date of low energy πN(3,3) resonance ρ resonance, the photo-production cross-sections of γ+q+q+π⁺+π- are calculated. The results are compared with the recent experimental data.