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1.
Computer calculations have been made on the dimensional solution to the anisotropic diffusion convection equation for solar cosmic rays propagating in an uniform and unbounded interplanetary medium. This paper presents the results calculated by means of Jokipii's diffusion coefficients. Discussion is restricted to the influences of solar wind convection on the rise to maximum times and on the peak intensities of solar cosmic ray events with solar corotation effect taken into consideration. The model well explains the asymmetrical variations of the propagation charateristics of the events with solar longitudes of their parents flares relative to the interplanetary magnetic field lines passing through the earth, and the theoretical curves of the rise times fit satisfactorily the observations of solar events ranging from relativistic to about 30 MeV medium energies.  相似文献   

2.
We give an approximate sequence for Ut,t0)-operator.We prove the follow-ing theorems:Theorem 1.If the norm ||Ht)|| of Ht)in equation(2.1)is a Lebesgue in-tegrable function with respect to t,then there is an approximate sequence{Un},such that for any state vector |Φ〉,|Ψ〉,the sequence <Φ|U1|Ψ><Φ|U2|Ψ>,......,<Φ|Un|Ψ>,......is uniform convergent with respect to t.Theorem 2.If in finite time interval,the norm ||Ht)|| of Ht)in equation (2.1)is a Lebesgue integrable function,then equation(2.1)has unique solution.  相似文献   

3.
The kinetic equation including a small-scale collisional integral for the particles propagating in a strong random and regular magnetic field [29] is solved by expanding the distribution function into series in spherical harmonics of the particle momentum angles. Using methods of the quantum theory of the angular moment [41], the equations for higher multipole moments of the distribution function in the space of momentum angles are derived and solved in the stationary case for the galactic cosmic rays in interplanetary space. The observed amplitudes and phases of the diurnal variation harmonics can be explained using the results of measurements of the interplanetary magnetic field performed on board the Ulysses spacecraft [12–14] and other satellites [45, 46] with an allowance for redistribution of the interplanetary and interstellar magnetic field lines. The spatial structure of the convection and diffusion fluxes of the galactic cosmic rays is refined. Formulas taking into account a change in the Earth’s axis tilt relative to the direction toward the Sun are derived, which allow the annual changes in contributions to the diurnal variation harmonics to be determined. The equation of diffusion taking into account the 2nd harmonic is obtained, and the contribution of this effect to the relative particle density in the cosmic rays in a spherically symmetric case is analyzed.  相似文献   

4.
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   

5.
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   

6.
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   

7.
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   

8.
We continue the investigation of the equation and its solutions for the bound states of mesons discussed previously, emphasizing on large values of v, a parameter characterizing the shape of the potential. The results show that the dependence of the eigenvalues λ and some related physical quantities upon the potential parameters v and E is approximately the same as in our previous work. But the average radii of the bound mesons cease increasing as v increases. For each value of v, there exists a maximum average radius√<R2>max, and all these √<R2>max are approximately equal to 12.6 M-1 (M being the mass of the straton), which is much smaller than the experimental value of the radius of the π meson. However, if we assume, in addition to the attractive potential, there exists, for the straton-anti-straton superstrong interactions, also a repulsive potential, and, in particular, if we introduce a differencetype potential VDr) corresponding to the potential Vvr) in our previous work, the calculated radii of the bound mesons do approach the experimental value.  相似文献   

9.
Using different approaches and techniques of wavelet analysis we analyze variations (oscillations) of galactic cosmic rays, solar spot number, and coronal index of solar activity before ground level enhancements of solar cosmic rays. Obtained results are discussed in frames of recent ideas about periodicity phenomena in the photosphere, and corona of the Sun, interplanetary medium, and cosmic rays.  相似文献   

10.
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   

11.
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   

12.

The scale-breaking parameter F2ep(x, Q2) of non-singlet component F2ep-F2en and some other quantities in the electro-production process are discussed by usinb the analytic expression for the distribution function of valence quarks in ha.drons up to leading log approximation given by a, previous paper[1]. Comparisons with data are also given.

  相似文献   

13.
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   

14.
Supposed that all of cosmic ray particles of energy below 3×1018eV are mainly originated and accelerated in an individual explosion of the galactic supernovae(SNs).By using an isotropic diffusion propagation model,non-steady state density of the iron nucleus is investigated.Considering the effect of extra-galactic cosmic rays and the variety of the galactic cosmic ray nuclei,the statistic model of galactic cosmic rays with a reasonable distribution of the SNs in space and time can account for the spectrum of cosmic ray in the energy range of 1012—1020eV quitewell.  相似文献   

15.
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   

16.
Enlarging the dimensionality of Minkowski space from 4 to 5,and relating the restmass of particle with x5 as m=—i&#8706;/(&#8706;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   

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.
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.
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   

20.
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   

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