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1.
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   

2.
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   

3.
Excitation curves for the reaction 27Al(n,α24Na,46Ti(n,p46Sc,48Ti(n,p48Sc,51V(n,α48Sc and 127I(n,2n126I have been measured by the activation method in the4.5—18.3 MeV energy region.The cross section for the reactio 27Al(n,α24Na was determined at 14.61±0.20 MeV.The measurement of neutron flux was performed using the associated particle method.The cross sections for other reactions were de-termined relative to the measured 27Al(n,α24Na cross section.The resulting activities were measured employing a calibrated NaI(TI)scintillation counter.The values obtained were 117.5±3.0 mb,291.4±14.0mb,63.7±3.2 mb,16.8±0.9mb and 1656±68 mb respectively.A brief comparison with existing data was made.  相似文献   

4.
The energy levels and transition probabilities B(M1) of the 208Pb 1+ states are calculated using the matrix diagonalized method in which the (1p 1h) configurations are coupled to collective octupole phonons. Calculated results show that the fine structure of the 208Pb giant magnectic resonance depends rather strongly on the phononparticle coupling constant.  相似文献   

5.
In this paper, the generate coordinator method (GCM) is applied to study the effect of multipole vibration on M1 transition of 1+ states in 208Pb. The calculation shows that coupling between 3 collective state and (1p1h) gives much more effect than the coupling effect of 2+ state with (1p1h).  相似文献   

6.
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   

7.
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   

8.
In this paper. we have used the Eikonal wave functionφE(r)=(2π)-3/2 exp(ik.r)X(r)whereexp{-i/hv∫-∞zV(x,y,z,')dz'}and V=nk/m to investigate the quasifree scattering 6Li (p, pd)α with Ep=156 MeV,590MeV and 670 MeV. In V(x, y, z), the nuclear interaction and the Coulomb inte-raction are included. For the case of 156 MeV, the nuclear potential is taken to be the Woods-Saxon type.The result is shown in fig. 1. This result is compared with those obtained by themethod of partial waves. For the cases of 590MeV and 670MeV, a new method is used to describe thenuclear potential, and the results are showh in fig. 3 and fig. 4, respectively.  相似文献   

9.
For reactions induced by light heavy ion such as 12C, at bombarding energy slightly above the coulomb barrier, using semi-classical theory, neglecting macroscopic frictional force, the reaction mechnisms are sorted by the orbital angular momentum of the entrance channel from the classical deflection functions fitting elastic scattering. Moreover, inserting a transfer probability factor representing the Q-Window effect into the semi-classical angular distribution formula of Kalinkin and Grabowski, we obtain a formula for the differential cross-section per unit energy interval. The calculated results, including the elastic scattering angular distributions, energy spectrum and angular distributions of emitted α-particles in quasi-elastic process, complete fusion cross-section, fusion-fission cross-sections and the exitation functions of evaporated neutron, agree with the experimental data on the reaction 12C+209Bi reported by our Institute.  相似文献   

10.
The cross section measurement for the reaction 56Fe(n, p)56Mn was made using the activation method from 12 MeV to 18 MeV. The absolute cross section was determined at 14.61±0.20 MeV, the value obtained was 108.0±2.7mb. The associated particle method was used to determine the absolute neutron flux and compared with the recoil proton telescope. The agreement between both methods appeared to be within 1—2%. The resulting 56Mn activity was measured by using a φ10×7.6cm NaI (Tl) scintillation counter. The counting efficiency of the counter was achieved by means of a standard 56Mn source calibrated by the 4πβ-γ coincidence method. The result measured was compared with existing data.  相似文献   

11.
The ground state of 6Li is investigated by means of the projected variational method for double well-cluster shell model. The results of the variational calculation show that the root-mean-square radius of d-cluster in the ground state of 6Li is smaller than that of free deuteron and as the mean distance between the α-cluster and the d-cluster decreases there are two effects on the d-cluster, namely contraction effect in which the d-cluster contracts first and then makes a bit extension and deformation effect in which the d-cluster makes oblation first and then streteches.It is also demonstrated by the calculation that the repulsive component of the odd sytate of N-N force and the pauli exchange of the nucleons between the clusters play an important role not only on the cluster structure in the ground state of 6Li but also on the contraction and the deformation of d-cluster in 6Li.  相似文献   

12.
It is shown that without exception the observed rms charge radius constants of strongly deformed nuclei, rp's, are a little larger than those of the neighbouring spherical nuclei. The local variations among the charge radii of the sequence of isotopes, the in complete neutron shells [1p3/2(N~3—6), 1d5/2(N~9—14), 1f7/2(N~20—28), 1g9/2(N~40—50), 1h11/2(N~70—82)], display some peculiar behaviors (eg. rms cnarge radii decrease with increasing A) which are sharply conflicting with the traditional A1/3 law. Taking the deformation effect into account, these strange variations can be accounted for with the Z1/3-law.  相似文献   

13.
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   

14.
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.  相似文献   

15.
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   

16.
Using the B-S wave functions of mesons in the massive straton model[1], we discuss their weak decay, electromagnetic decay, and particularly hadronic decay processes. Not only fπfK, 1l+l rate are successfully explained, the predicted widths for various hadronic decays are also in good agreement with experimental data.  相似文献   

17.
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   

18.
In this paper, we analyse the commutation relations of the infintesimal opera-tors of the group SU3 and find that the eight infinitesimal operators of the groupSU3 can be written as a scalar operator A, three angular momentum operators (L1,Lo, L-1,)and two sets of the irreducible tensor operators of rank 1/2, (T±1/2,V±1/2)By means of the commutation relations of these operators, all irreducible represen-tations of the group SU3 can be easily obtained. In this pape, the matrices corresponding to these operators in the irreduciblerepresentation(λμ), are given; therefore the irreducible representation and its re-presentation space Rλμ are completely defined. Besides, a method for calculatingthe scalar factors of the reduction coefficients and the symmetric relations of thosefactors are also given. As examples, the scalar factors of the reduction coefficientsof (λμ)×(10), (λμ)×(01), (λμ)×(20) and (λμ)×(11) are calculated. In the last part of this paper, we define the irreducible tensor operators ofthe group SU3 and prove the corresponding Wigner-Eckart theory. The method used in the discussion of the group SU3 be extended to allof the compact simple Lie groups of rank 2 and we shall discuss them in two suc-ceeding papers.  相似文献   

19.
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   

20.
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   

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