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1.
In this note we propose that the electromagnetic self energy of lepton may beconnected with quantum number n by( (δm)/m)=(1/(2π))n-b ,in which b is a constant.Wefnrther propose that the cut-off value of momentum M is connected with gravitationalconstant κ and fine structure constant α by M=(1/√καe-1-b.So we obtainthe mass formula of charged leptons M=(1/√κα exp{-3/4-b-(1/3α)n-b}.By using the masses of e- and μ- and the value of a as in put,we get the calculatedvalues of κ=(6.67231±0.00026)×10-8cm3g-1sec-2and mr=(1782.306±0.078)MeVwhich agree very well with experimental values κ=(6.6720±0.0041)×10-8cm3g-1sec-2 and mτ=(1782-4+3)MeV respectively.The mass of the fourth charged leptonpredicted by the formula should be m=(11725.47±0.51)MeV,which can be checkedby experiments in the near future.We also discuss briefly the proposed formula andthe obtained results.  相似文献   

2.
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   

3.
The cancellation properties of the nonhermitian single-particle (SP) potential uαβ=Mαβεβ) [or Mαβεα)] according to the principle of maximal cancellation of perturbation diagrams are investigated in detail. The mass operator Mαβω) is separated into two parts Mαβonω) and Mαβoffω) as usual, however, a new criterion for their definition will be proposed. It is shown that the exact mass operator insertion is equal to the sum of the following three types of terms:(1) terms contributed by the poles of Mαβoffω). They are truly non-factorizable and must be considered separately,(2) terms which can be cancelled to all orders by the nonhermitian choice uαβ=Mαβεβ) [or Mαβεα)]. Hence, they serve to define uαβ,(3) the remaining terms, which can be summed to all orders in a simple way and may be interpreted as amplitude renormalization of the SP Green function.In order to illustrate the usefulness of the above results, we have considered the renormalized random phase approximation (RRPA) for the particle-hole Green function as an example. Related formulae are derived. In RRPA, not only the SP propagator renormalization which includes all the effects except those contributed by the poles of Mαβoffω), but also the off energy shell property of the G matrix elements have been taken into account.  相似文献   

4.
Two processes ψ(2S)→π+πJ/ψ,J/ψ→1+1 and J/ψ→anything are carefully studied to get the J/ψ leptonic branching fractions with the ψ(2S)data at BES/BEPC.The results are B(J/ψ→e+e)=(5.90±0.07±0.16)% and B(J/ψ→μ+μ)=(5.96 ±0.08±0.16)%,and Be/Bμ is estimated to be 0.990±0.018±0.024.Assuming Be=Bμ,the leptonic branching fraction of the J/ψ is B(J/ψ→1+1)=(5.93±0.05 ± 0. 16 )%.This result is used to estimate the QCD scale factor ∧(nf/MS) and the strong coupling constant αs.  相似文献   

5.
A relativistic equation of motion of a two particle system under the constraints pi2-mi2-U(x2)=0.(i=1,2), where U(x2) is an infinite spherical square well poten-tial, is applied to the SU(4) quark model of mesons. A set of linear mass relations areobtained. Instead of the linear relation between J and M2, the Regge trajectory ob-tained is a relation between pnl2 and M2, where ζnlπ are zeros of the spherical Besselfunctions. The new trajectory seems more satisfactory than the former one.  相似文献   

6.
The effects of the coupling term between field(Y0σ11v and r2Y2σ11v coming fromtensor operator are discussed for the spin gaint dipole resonance.The effects of inclu-ding the field rλ+1(Yλ+1σ1)λv on the spin gaint multipole resonance and core polariza-tion are considered.  相似文献   

7.
The properties of fermion causal Green's function is discussed according to the theory of spectral representation. The definition of effective mass is established from the view point of field theory, and the approximate expression of SF' (p) as |p2|«M2 and the asymptotic formula of SF' (p) as p2→+∞ is given. In terms of these result the problem of quark confinement is discussed. We find that: (ⅰ) Based on the theory of spectral re presentation the concept of relative confinement is allowed, and if renormalization effect is strong, the quarks can demonstrate definitely lighter effective mass when they are far away from the mass shell; (ⅱ) Based on the theory of spectral representation the concept of absolute confinement is unallowable, even the absolute confinement is taken as the limit of relative confinement. That is if the concept of absolute confinement is introduced, we must discard a part of elementary hypothesis of spectral representation theory.  相似文献   

8.
A subquark model is proposed. According to this model, stratons and leptons are consisted of rishons T and V, which are multiplets of group SUH(3)×SUC(3)×SUG(2)×SU(2)×U(1). Three generations of both stratons and leptons are obtained naturally. In this model, proton decay modes are μe+e+ or eμ+μ+.  相似文献   

9.
Due to the possible production of neutral and charge heavy leptons by vμ, models consisting of four elements per "line", e.g. ve, e-, E0, E- vμ, μ-, M0, M- vτ, τ-, T0, T- ……are analysed. Non-diagonal neutral currents cannot be avoided. Nevertheless, a model is proposed within SU(2)×U(1) in which the process μ can still be suppressed by the Bjorken-Lane-Weinberg mechanism; various production cross-sections for heavy leptons are reasonable when compared with experiments. Models corresponding to SU(3)×U(1) and still higher symmetries are discussed.  相似文献   

10.
Enlarging the dimensionality of Minkowski space from 4 to 5,and relating the restmass of particle with x5 as m=—i∂/(∂x5)))we discuss the 5-dimensional non-linear con-formal group CM5)under which dx12+dx22+dx32-dx02+dx52=0 is invariant.The CM5)group is isomorphic to the linear group SO(5,2)from which we study thespace-time property of Fermion number,and the relations between half-integral(in-tegral)spin and odd(even)Fermion number are obtained.  相似文献   

11.

The decay channel ψ′→π+πJ/ψ(J/ψ→γpp) is studied using a sample of 1.06×108 ψ′ events collected by the BESIII experiment at BEPCII. A strong enhancement at threshold is observed in the pp invariant mass spectrum. The enhancement can be fitted with an S-wave Breit-Wigner resonance function with a resulting peak mass of M=1861+6-13 (stat)+7-26 (syst) MeV/c2 and a narrow width that is Γ<38 MeV/c2 at the 90% confidence level. These results are consistent with published BESII results. These mass and width values do not match with well established mesons.

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12.
A method for finding potentials corresponding to polynomial-factor eigenfunc-tions is given for the Schr(?)dinger equation as an example.It is shown that theeigen-solutions for harmonic and Columb's potentials in quantum mechanics are the twoexamples which can be given by this method and some other examples are discovered.This method and some results of this paper may be useful for hadron structure mo-del theory.One of the examples is the equation in Ref.(4)which is derived fromBethe-Salpeter equation for the case that the straton is tightly bounded in certain po-tential well.When this method is applied to that equation for three dimensionalcentral symmetric potential V(r)=V0—2(N+(1/2))β-1(√V6r2)+(V6r6), some resultsare obtained as shown in Fig. 2 in which λ′ must be considered as a linear function of m2.The so called“quasic Regge trajectory”behavior is manifested.  相似文献   

13.
By assuming that in a high energy hadronic collision process,N pairs of stratonsare produced together with gluons,the number of which is supposed to be propor-tional to the number of“bonds”between any two stratons,we are able to get a rela-tion between the Q-value and the number of pairs N:N=(α2+βQ1/2-α.The average charged multiplicity〈nchtheo is calculated,and is compared withthe experiments.The data of pp、π±p、K±p collisions all coincide with the theoreticalcurve in a wide range of energies.The deviation between the energy vs.chargedmultiplicity relations for meson-proton and proton-proton collision processes are ex-plained quantitatively.The average straton mass estimated from the theory is ingood agreement with that.given by other authors.  相似文献   

14.

We present a study of the inclusive photon spectra from 5.9 million J/ψ decays collected with the KEDR detector at the VEPP-4M e+e collider. We measure the branching fraction of radiative decay J/ψ→ηcγ, ηc width and mass. Our preliminary results are: Mc)=2979.4±1.5±1.9 MeV/c2, Γc) = 27.8±5.1±3.3 MeV, B(J/ψ→ηcγ)=(2.34±0.15±0.40)%.

  相似文献   

15.
The Technicolor(TC)O(αmt2/mw2)corrections to top pair production in high energy e+e annihilation are calculated in the one generation TC model.The analytic expressions are given for the form factor, the renormalized matrix element and its square.Numerical examples are presented for the corrections to the total cross-section ,the forward-backward asymmetry AFB and the left-right asymmetry ALR.We found that the corrections can reach -12.3%, -3.3% and -11.7% to the observables,AFB and ALR respectively for the favorable parameter values.The level of these corrections might be achieved at the next-generation linear collider(NLC).It might open a window for testing TC theory.  相似文献   

16.
In this paper the Gamow-Teller transitions are systematically investigated for nuclei with A=147-1.53 in terms of the shell-model. These nuclei have only GT decay channel π1h11/2→v1h9/2. The overall comparisons of the experimental reduced probabilities Bexp(GT) with the calculated Bcal(GT) show that there is a quenching factor γ2 with optimum value 0.17±0.05 in this mass region.  相似文献   

17.
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   

18.
If the antiproton optical potential is inclusive of the spin orbit interaction term,the A(p,p)A* inelastic scattering not only can excited the normal parity states,but also can excited the abnormal parity states.There are also induced the polarization Pf(θ) at the inelastic scattering.In the framework of DWIA,we derived the inelastic scattering cross section (dσ/dΩ)f,i,and polarization Pf(θ),and calculated the (dσ/dΩ)f,i, and Pf(θ) for 12C(p,p)12C* with 2+,3 and 1+ states at antiproton energies of 46.8 and 179.7MeV.They fited experiment data quite well.Due to the abnormal partity states in the inelastic process have been measured,the spin orbit term can not be neglect.  相似文献   

19.
In this paper,we suggest a two-nucleon model of the A(p,π-) B reaction.Areduced formulation of the reactoin amplitude and a relation between the reactionamplitude and the nuclear structure are given.The differential cross section of 13C(p,π-14Og.s,at EP=185 MeV is calculated in the plane wave approximation.The results+s can explain the experimental data qualilatively.  相似文献   

20.
At an altitude of 3220 meters above sea level in Yunnan Province, we measured, by using a G-M counter-magnetic spectrometer, the vertical integratted momentum spectrum of the cosmic muon with momentum larger than 4 GeV/c. The spectrum obtained from this experiment is expressed by a power function in the form of I(>p)=Qp+4)-1.86±0.06(cm-2·sr-1·s-1), where p is in GeV/c and Q is a constant. We also measured the charge ratio of muon in the 4—23 GeV/c momentum range. The result is Nμ/Nμ-=1.26±0.11. The error in the momentum measurement with spectrometer has been discussed and calculated.  相似文献   

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