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1.
Under the framework of the Bakamjian-Thomas theory,we discuss the qualitativeproperties of the phenomenological nuclear force V=VR-iV1 at high energy arediscussed by a comparision with the small angle scattering data.Because these data inhigh energy are insensitive to the spin,we suppose that the nuclear force at highenergies is spin-independent.The followings are obtained:i)for the Gaussian potential,X3≌200 MeV and β3≌0.95 fm,which are thestrength and the range of V1 respectively;ii)in VR,there is no hard repulsive core.Under a rough estimation,supposingthe range β1>0.45 fm,we find the strength of the repulsive force,X1<480 MeV;iii)all parameters are vary very slowly with energy.  相似文献   

2.
The behavior of the phase-shift of the Bakamjian-Thomas theory and its relationwith the phenomenological nuclear force V=VRiVI at high energy are explored.Two limits are obtained:It is found that the repulsive core with a sharp outer edge may induce a characteris-tic oscillation of Re δ1,and Im δ1 is sensitive to V1.The conclusion is that the analy-sis of the phase-shift extending to higher energy is relevant in determining therepulsive core and the imaginary part of the nuclear force.  相似文献   

3.
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   

4.
Starting from the state density formula which accounts for proton-neutron distinguish ability, a modification for complexparticle emission probability in the preequilibrium exciton model is given, which modified the complex-particle emission probability Wαβ and the pure combination probability Rαβ given by C.K.Cline and I.Ribansky et al. The calculated results by using modification formula are in better agreement with the experimental data compared to that of Cline and Ribansky.  相似文献   

5.
We point out the possible existence of bosonic charged partons (diquarks) withinnucleons. A certain form of the structure functions of diquarks inside nucleons is as-sumed and the functions are suitably parametrized. Then, by combining their effectswith the usual QCD calculations, we get a better theoretical fit to the experimental R=(σL)/(σT) value in e-p deep inelastic scattering.  相似文献   

6.
Using the fact that the proton contains the Charm State │uudcc〉 and combining its effects with the result of the usual calculations of A.J. Buras et.al., a better agreement of the theoretical value of the ratio RLT in e-p deep inelastic scattering with the experimental data is obtained.  相似文献   

7.
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   

8.
By means of the generalized method of quantum expansion and the general treatement for quantization of gauge fields recently proposed by S. N. Gupta, we calculate the quantum expansion around the vertex type solution of N-O model. Under special conditions, the eigen-value of the energy of quantum excitation can be obtained.It is shown that both Po(-1) and IIo (-1) are equal to zero in the case we considered. As a result, our calculations are greatly simplified.  相似文献   

9.
In this paper a new bag model of hadrons,the“Rubber Bag”model,is proposed.This model treats each hadron as a bag system in the centre-of-mass frame.The bag,with its outer radius Re and inner radius(Rc-D),is characterized by its“averagesurface tension”T and the quarks are confined in it“temporarily”.This model isa field theoretical model which can also be used for quantitative calculations.Thus,ithas the merits of the SLAC bag model as well as those of the MIT bag model.  相似文献   

10.
We discuss the CP violation problem of SU(7) models of Grand Unified Theoryincluding four genarations[1,2]. It is shown that if we properly choose the complex phaseangles in quark mass matrix elements, we are able to obtain the CP violation phaseangle which agrees well with the experimental value. If the Higgs potential is pro-perly choosen we find that the strong CP violation parameter θ is equal to zero atthe tree level.  相似文献   

11.
In Rξ gauges a SU(2)spontaneonly broken gauge theory is qnantized within the canonical formalism,and the gauge compensating term is derived.  相似文献   

12.
The gauge field theory is formulated via loop phase factors with a fixed point O as their initial and final point. Let G be the gauge group. When the base space is the Minkowski space E4, we introduce a set of standard paths Ox (for example, the set of line segments Ox), where x is arbitrary. The phase factor for the infinitesimal loop Oxx+dxO corresponds to an element in the Lie algebra g and can be expressed as a g-valued differential form kx, dx) which satisfies the following conditions of consistency (a) kO, dx)=0, (b) kx, v)=0, where v is the tangential vector of Ox at x. It is shown that an equivalent class of gauge fields is determined by kx, dx) or (ad akx, dx) where a is a fixed element of G. Hence if we adopt k(x, dx) for the fundamental physical quantity of a gauge field then a great part of gauge indefiniteness is eliminated. Moreover if the phase factors Φxo for standard paths Ox are given then the phase factors for differential arcs x x+dx are easily calculated, and hence a gauge field in the equivalent class is extracted. We call the set of phase factors for standard paths a gauge and kx, dx) may be interpretated as the gauge potential under a special gauge under which Φxo=the unit element of G.The method is useful in considering the equivalence problem and the spacetime symmetry of gauge fields. For example, it is quite easy to determine all spherically symmetric gauge fields if they are free of singularities. By using the method it can also be proved that if two gauge fields have the same gauge and the same field strength then their gauge potentials are equal to each other. Consequently, under a given gauge in the above sense the field strength determines the gauge potential completely.For a general base manifold Mn, every equivalent class of gauge fields over Mn can be defined by loop phase factors also. In this case, Mn is expressed as the sum of a set of neighborhoods each of which is homeomorphic to the Euclidean space. The standard paths are constructed according a certain rule, the phase factors for standard differential loops are also introduced. The transition functions and gauge potentials of a gauge field in the given equivalent class are derived as the phase factors for some finite loops and standard differential loops respectively. Further it is remarkable that a global gauge field is determined completely by the field strength and some discrete loop factors, if the phase factors for the standard paths are gwen.In mathematical terminology principal G-bundle structure as well as a connection in it is determined by the holonomic mapping which maps the set of loops through a fixed point into the group G, provided the mapping is differentible in a certain.The author is very grateful to Prof. Yang Chen Ning for many helpful discussions.  相似文献   

13.
A quark-quark potential is derived from the linear expression of the Lagrangian Which is invariant under the SU(3)L×SU(3)R infinitesimal transformation,and further used to make a qualitative analysis on the Λ-N interaction.The result shows that the SU(3)chiral scalar fields are important in explaining the spin-dependence feature of the Λ-N interaction.  相似文献   

14.
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   

15.
The difficulty of the classical dynamics in studing the mechanism of angular momentum transfer is discussed. According to the nuclear rotational concept formed in the study of the nuclear structure for a long time, we point out that it is convenient to divide the total angular momentum I transfered to the target and the projectile into two components-the nuclear collective angular momentum IR and the rotational alignment angular momentum Ij.  相似文献   

16.
Let F be a SUN gauge field on the space-time manifold M4, bλx) (λ=0,1, 2, 3) the gauge potentials, the field strengths and Qx) a Higgs field. All quantities b, fλμ and Qx) are SUN'-valued, i.e. they are represented by N×N anti-hermitian traceless matrices.Let M4' be the set of x such that Qx)≠0 and define on M4', where The following results are obtained:Theorem 1. The 1st set of Maxwell equations Fλμ,v+Fμv+Fvλ,μ=0 are satisfied for arbitrary bλ if and only if with Here s is an integer, 1≤sN-1.Suppose the conditions in theorem 1 are satisfied.Theorem 2. If s is a space-like two-dimensional surface, the value of dual charges contained in s defined by is equal to lq', where l is an integer and Theorem 3. The value of dual charges contained in S is equal to the integral which is independent of the gauge potentials.Theorem 4. The least positive value q' of dual charge can be attained by some Higgs fields.Remarks(a) When N=2, the results obtained are consistent with those of t Hooft, Arafune and Hou etc.(b) For N=3, we give an answer to the question of quantized values of dual charges which was discussed by Marciano and Pagels.(c) The Higgs field ø(x) is a mapping from M'4 into the AⅢ type symmetric space SUN/S(Us X UN-s) and the integral is an extension of Kronecker index for N=2.  相似文献   

17.
The influence of the self-energy diagrams on the solutions of the Bethe-Salpe-ter equation is studied by taking a gφ1*(xφ1xφ2x) interaction and under the ladder approximation. The results show for ground state solution, the self-energy diagrams will diminish the eigenvalues and alter the wave funetions slight-ly. While for the excited states and anti-symmetric solutions, the influence of theself-energy diagrams is considerable. which completely alters the properties of the solutions. The results also show that the solutions from the ladder approximationare meaningful only in the loosly bounded cases, and as the binding becomes tight,the contribution from the self-energy diagrams becomes important.  相似文献   

18.
In this paper, the folding potential of the double well-cluster shell model fol-ding potential is derived. We use this potential to calculate the α-α elastic scatter-ing up to 27 MeV energy. the theoretical results agree with experiments rather well.It shows that for heavy-ion elastic scattering, the intrinsic state excitation should betaken into account properly.  相似文献   

19.
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   

20.
Suppose that a high energetic proton interacts with a cluster of m particles in anucleus the mean multiplicity of this interaction and that of PP interaction followthe same law: n=CSk. Using the Glauber theory we get R(A)≡nPA/nPP1.26A 1/3(A 1/3+1) -2/3 This formula explains the current experimental result quite well.  相似文献   

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