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1.
In this paper we work out the relativistic covariant B-S wave function for the(π+ π-s atoms.Some properties of the“direct channel diagram”of the produc-tion the (π+ π-s atoms are discussed by calculating the cross-section of the process π+ +np+(π+ π-s with the help of the relativistic covariant wave function and assuming the lowest termin the perturbation expansion series of the quantized composite field theory——the“direct channel diagram”is dominant.Besides this calcuation perhaps presentsa rough estimate for the interesting process μ+ +n→(μ+ π-)+p.  相似文献   

2.
Hadronic production of J/ψψ′(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.  相似文献   

3.
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.  相似文献   

4.

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.

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5.
The group chain U5O5SU2×SU2 used by K. T. Hecht (1965) and by the othersprovides an important representation for expressing the physical basis of d-boson sys-tems. However the methods which have been introduced for this SU2×SU2 representa-tion to construct a physical basis is poorer in comparison with those for the otherrepresentations. In view of this we try to find appropriate methods to obtain the SU2×SU2 representation wave functions of the existing physical bases constructed byChacon et al. and by Szpikowski et al., In the present paper we analyse the SU2×SU2 tensor properties of the,bosonoperators and Vilenkin's traceless boson operators and express succinctly the elementaryvectors of the SU2×SU2 basis, the |PP SU2×SU2 > vectors, in terms of the tracelessoperators. With the help of this form of the| PP SU2 SU2> vectors we derive a simpleformula for obtaining the SU2×SU2 -representation wave functions of a physical basisfrom its (nμ)-representation wave functions. Thus the problem mentioned above is partlysolved. The other parts of the solution of the problem will be found in a coming paper.  相似文献   

6.
The comparison of two fragmentation schemes used in the analysis of e+e annihilation are presented in this paper.It is found that the independent fragmentation assumption is strongly disfavored by the data of the final particle multiplicities,and the string fragmentation assumption agrees with experiments.  相似文献   

7.
Calculations have been performed for the energy separation of the two major substitutional states of the hypernucleus 40ΛCa. The (K) cross sections are calculated in the framework of the distorted-wave impulse approximation. Information about the ΛN interaction is then extracted, particularly, on the effects of the strength parameters on cross sections. The result shows that the ΛN interaction adopted previously for the 1p shell hypernuclei might be suitable to use for the (K) reaction in which medium heavy hypernucleus 40ΛCa are produced, but the value for the strength parameter of the central potential has to be changed from 0.99 to 0.78.  相似文献   

8.
We discuss the suppression of the decay of heavy lepton τ into πvτ,by assuming that τ and/or vτ carry spin 3/2. For the case of spin 3/2 T and spin 1/2 vτ, using the weak current ψμ(τ)(a+bγ5)Ψ(vτ)we find that the πvτ decay channel relative to the vτvll-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.  相似文献   

9.
A series of Y123 single phase samples with various Ba vacancy concentration was prepared by making their Ba contents deviate from the stoichiometric composition. The measurements of their structure, superconductivity and flux pinning behaviour were systematically carried out. It is found that, compared with YBa2Cu3O6.96 sample, the strength of the flux pinning in YBaxCu3O7-δ(1.8≤x<2.0) samples is increased, and that there is an optimum value of Ba vacancy concentration for the maximum flux pinning force density. The possible origin of the flux pinning centers to determine the flux pinning behavior at higher field is discussed in detail. We suggest that the flux pinning effect at lower field may stein from the interaction between the vortex and the surfaces of grains, and that the flux pinning mechanism at higher field belongs to the core interaction.  相似文献   

10.
The excitation functions of the 23Na(p,α020Neg·s.and the 23Na(p,α120Nelst reae-tion have been measured from Ep=1 to 2.5 MeV at θL=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.  相似文献   

11.
The question of the relationship between the frequencies of injector linac and storage ring is analysed, especially when sub-harmonic buncher is used. In that case, it seems to be necessary to keep the ratio of two frequencies of the linac and storage ring to be an integer. This question is discussed in detail in this paper from several points of view. As a result of the discussion, two suggestions to avoid the restriction on the frequency relationship are presented.  相似文献   

12.
We show that the near correlation in rapidity is consistent with the requirements of QCD, and completely determines the combination rule of quarks. We give the formulae for calculating yields of mesons, baryons and antibaryons, which are produced by a stochastic accumulation of quarks with similar rapidities. Using it to e+e annihilation, the observation of recently unexpected copious production of baryons is explained naturally.  相似文献   

13.
The energy spectra and angular distributions of alpha particles emitted in the reaction of 12C on 209Bi in the energy range 61.1—73.0 MeV were observed.The △E— E detector system was used to separate alpha particles and other particles emitted in this reaction.The results can be interpreted in terms of the reaction mechanism,in which a 8Be cluster is transfered from the projectile to the target.Good agreement has been obtained between the cross section for the production of the direct alpha particles and that of the heavy residue 217*Fr which,left in the ground state after evaporation of 2 neutron's,decays into 211At by alpha emission.The experimental energy spectra and angular distributions have been fitted by a semi-classical formula for the differential cross section per unit solid angle and energy interval.  相似文献   

14.
In this paper,we have analyzed the experimental results of the quasifree scattering6Li(p,pda with Ep=156 MeV.Both PWIA and DWIA are performed.UsingDWIA and the relative wave function proposed by Sakamoto et al.,the results of ourcalculation agree better with the experiment.  相似文献   

15.
The change of the internal energy of the α-particle is usually neglected in the previous calculations of the binding energy of 5He.The present work shows explicitly that the change of the internal energy of the α-particle can influence significantly the theoretical value of the binding energy of 5He.  相似文献   

16.
Angular distribution of the scattering of 31.2 MeV-α-particle by the nucleus 10,11B is measured. Our results show that there is anomalous phenomenon in the case of 10B but there is not in 11B. Calculations and analysis are made with the optical model adding the Regge-Pole model. The results show that for the nucleus of 1p-shell, such as α+16O, the result of the calculation agrees very well with the experimental measurements but it fails in α+10B. As to the analysis with the double v-power optieal model for α+16O, the agreement is somewhat a little worse than the former's and the result for α+10B agrees only qualitatively with the experimental measurement. It is well known that the analysis with these models for α+40Ca agrees very well with the experimental data. Thus we may come to the conclusion that the mechanism of ALAS of the nucleus of 2s-1d shell is different from that of 1p-shell, and the mechanisms of ALAS of the nuclei of 1p-shell are also different.  相似文献   

17.
In this paper,we suggest that the gluon is hadronized by first splitting into a quark-anti-quark pair.The final hadrons are produced by the color interactions among the quarks and antiquarke.By this assumption,the calculated average charged particle multiplicities in e+e→3jet events,and the ratio of multiplicities between gluon and quark jet,and the rates of baryons in e+e three gluons events all agree well with experiments.The angle distribution of final particles can be explained.  相似文献   

18.
The two-particle scattering phase shifts with a λφ4 +ξφ6 interaction are com-puted in (1 + 1) and (2 + 1) dimensions using the Gaussian wave-functional approach.Through numerical analysis, we give the phase-shift curves with respect to the scat-tering energy for most cases of this theory. In (1 + 1) and (2 + 1 ) dimensions, for the symmetry vacuum the phase shifts are positive or negative depending on the signs of the renormalized parameter, while for the asymmetric vacuum the phase shifts are negative.  相似文献   

19.
The energy spectra of the alpha particles from the reaction 141Pr (n, α) 138La at 0°, 30°, 60°, 120°, 150° and 180° are measured and the angular distributions of the alpha particles are given. It shows that the predominant mechanism of the reaction at En=14 MeV is precompound emission.  相似文献   

20.
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.  相似文献   

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