The Strong Coupling SU(3) Limit in IBM4

When the IBM is generalized and used to the case of light nuclei,it is called IBM4.In this paper,for the following group chain of the IBM4 U(36)U₆(sd)×U₆(ST) SU₃(sd)×SU₃(S)×SU₃(T) SU₃(sdS)×SU₃(T)× O₃(J)× O₃(T) the reduction rules,typical energy spectra and E2 transitions are discussed.Using this strong coupling SU(3) limit,the nuclei in sd shell are classified.     

A STRUCTURE MODEL OF STRATONS AND LEPTONS

A subquark model is proposed. According to this model, stratons and leptons are consisted of rishons T and V, which are multiplets of group SU_H(3)×SU_C(3)×SU_G(2)×SU(2)×U(1). Three generations of both stratons and leptons are obtained naturally. In this model, proton decay modes are μ^－e⁺e⁺ or e^－μ⁺μ⁺.     

SU(3) LIMIT OF U(6/20) SUPERSYMMETRY IN NUCLEI

In this paper we discuss the SU(3) limit of U(6/20) supersymmetry. First we derive the reduction formulas of the relevant group chain. Then we discuss the dynamical symmetry. Finally we make comparison between the theoretical calculation and experimental measurement in the case of nucleus .²³⁵₉₂U₁₄₃     

Constraint on the warped space from B→X_sγ

We analyze the theoretical prediction on the branching ratio of B→X_sγ to order Λ_EW²/Λ_KK² in extension of the standard model with a warped extra dimension and the custodial symmetry SU(3)_c×SU(2)_L×SU(2)_R×U(1)_X×P_LR, where Λ_KK denotes the energy scale of low-lying Kaluze-Klein excitations and Λ_EW denotes the electroweak energy scale. Contributions from the in nite series of Kaluze-Klein excitations are summed over through the residue theorem. The numerical result indicates that the present experimental data constrain the parameter space of the concerned model strongly.     

U(B)(6)×U(v)(12)×U(π)(4) DYNAMICAL SYMMETRY IN ODD-ODD NUCLEI

SO^(Bvπ)(6) limit of U^(B)(6)×U^(v)(12)×U^(π)(4) dynamical symmetry in odd-odd nuclei is discussed Energy formula and wave functions are obtained,and exaetd expressions for E₂ trasition rates and and one-nucleon transfer intensities are derived.The spectra of ¹⁹⁸Au₁₁₉ and ¹⁸⁸Ir₁₁₁ are compared with the exprimental values.     

AN SU(4)×SU(2)×U(1) UNIFIED MODEL

In this paper we propose an SU(4)×SU(2)×U(1) unified model, in which the stratons and leptons of every generation belong to the same Multiplet, and the leptons will couple to the stratons. But this kind of coupling cannot cause the proton decay, and has only some effects in high energy scatterings. This model predicts the existense of two neutral intermediate bosons, instead of one, and the value of Weinberg angle to be sin²θ_w=0.25. The neutrinos have reasonable masses in the model.     

U(6/20) SUPERSYMMETRY IN NUCLEI AND ITS Spin (6) LIMIT

The U(6/20) supersymmetry is discussed in this paper. Particularly we discuss its Spin (6) limit. First we discuss the reduction of the group chain of the Spin(6) limit. Secondly we derive the wave functions and excited energy formulas for the nuclei in which the Spin(6) limit of U(6/20) supersymmetry exists. Thirdly we make comparison of the nuclear energy spectra between the theoretical calculation and experimental measurement in the case of nucleus ₇₇¹⁹³Ir₁₁₆. The comparison shows that the Spin(6) limit of U(6/20) supersymmetry possibly exists in nucleus ₇₇¹⁹³Ir₁₁₆.     

THE SU(6) “UNITARY ENERGY BAND” STRUCTURE IN THE TRIBARYON SYSTEM

A picture of the tribaryon system is proposed based on the papers [1—3]. It is considered that proton, neutron and A hyperon from the basic particles of SU(3) group and form the basic particles of SU(6) group on account for spin. It turns out that there exist "unitary energy band" structure in the tribaryon system. From the mass formula of T₃³ breaking, one can find that the SU(6) symmetry gives the mass relations between different spin levels of the same strangeness analog states. Finally, simple calculations are made and tbere is no discrepancy between tbe results and the experimental data.     

DISCRETE SYMMETRY AND SU(N) GRAND UNIFIED MODELS

Using discrete symmetry S, a systematic analysis of all possible GUT models based on the low rank group SU(N)×S is presented. It is found that only SU(7)×S and SU(8)×S are the satisfactory gauge groups of flavour grand unification. In addition, SU(7)×S and SU(8)×S models are discussed in detail. All these models can accommodate. four generations of ordinary fermions and preserve the asympotic freedom of SU_c(3).     

THE SPECTROSCOPY OF FOUR-BARYON SYSTEM

In this paper, using SU(6) symmetry theory four-baryon system is discussed and a method of analyzing experimental spectra is provided. Because of the gound states of _ΛΛ⁴H, _ΛΛ⁴He_{, Λ}⁴He and ⁴He are in the same I. R. of SU(6), on can derives masses for _ΛΛ⁴H, _ΛΛ⁴He from the experimental data of _Λ⁴H, _Λ⁴He, and ⁴He. Calculation shows that these J^π=0⁺ double Λ hypernuclei _ΛΛ⁴H, _ΛΛ⁴He are not likely bound states.     

AN ANALYSIS OF FOUR-ELEMENT MODELS OF LEPTONS AND NON-DIAGONAL NEUTRAL CURRENTS

Due to the possible production of neutral and charge heavy leptons by v_μ, models consisting of four elements per "line", e.g. v_e, e^-, E⁰, E^- v_μ, μ^-, M^0, M^- v_τ, 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→eγ 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.     

Hierarchy of symmetry breakings and neutral currents in anSU(6) grand unification model

In anSU(6) grand unification model with eight quarks and eight leptons belonging to 15-plet and singlet representations, the symmetry is spontaneously broken by the sequenceSU(6)SU(3) ^c ×SU(2)×U(1)×U(1)SU(3) ^c ×U(1). Fror two cases of symmetry breakings the effective weak neutral current coupling constants are compared with experiment. For theSU(3) ^c ×SU(2)×U(1)×U(1)×SU(3) ^c ×U(1) symmetry breaking, the coupling constants reproduce the Weinberg-Salam model with a small correction term. Agreement with the experimental mean values is improved with the correction term. Parity violation in atomic physics is also discussed.     

THE SU2×SU2 BASIS AND THE PHYSICAL BASES FOR THE STATE VECTORS OF d-BOSON SYSTEMS AND THE TRACELESS BOSON OPERATORS (Ⅰ)

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 (n_μ)-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.     

THE REGGE TRAJECTORY OF MESONS AND THE SU(4) MASS RELATIONS

A relativistic equation of motion of a two particle system under the constraints p_i²-m_i²-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 p_nl² and M², where ζ_nlπ are zeros of the spherical Besselfunctions. The new trajectory seems more satisfactory than the former one.     

The Spin Crisis of the Proton

The relationship between the Gerasimov-Drell-Hearn(GDH)sum rule and the first monent,ΓP-the proton spin dependent structure function integral,is established.According to the sum rule and quark structure model of baryon,[SU_sf(6)⊙O(3)]⊙SU_c(3),the spin problem of the proton is discussed The present theoretical results are also compared with the data measured by EMC and SLAC groups.Our prediction is in good agreement with the data.We find that the P₃₃(1232)photo-cxcitation dominates the spin structure function integrals and contributes negatively at low momentum transfer.At higher momentum transfer,the contribution of the P₃₃ is positive,and it decreases rapidly as Q² increasing and finally becomes negligible The integral changes its sign from negative into positive at about Q²=0.3GeV².     

Vector Coherent State Representations of SU3 in U1 U1 Basis

In this paper,Vector Coherent State (VCS) representations of SU₃ in U₁ U₁ basis are discussed.Orthonormal basis vectors for SU₃ U₁ U₁ are derived and the multiplicity of a weight for SU₃ U₁ U₁ is determined by using K-matrix technique.     

WAVE FUNCTIONS WITHOUT SU6 SYMMETRY IN THE STRATON MODEL AND THEIR APPLICATIONS

On the basis of the straton model^[1],using the general groundstate wave functionsof mesons and baryons given in ref.[2],we have constructed under some specific as-sumptions the meson and baryon wave functions without SU₆ symmetry.We applythese wave functions to explain the mesonic and baryonic properties of the electroma-gnetic and weak interactions;many results obtained are in agreement with the experi-ments.By using the 1/2⁺-baryon wave functions without SU₆ symmetry,we obtain ananomalous magnetic moment for the proton.There is no need to introduce an ano-malous magnetic moment for the straton in the effective Hamiltonian of electromag-netic interaction between stratons.Similarly,the magnetic moment of the neutroncan also be explained.     

ΛΛ,ΛΛγ and ΛΛπ0 Productions in J/ψ Decay

The channels of J/ψ decay into,ΛΛ,ΛΛγ and ΛΛπ⁰ are analyzed with 7.8×10⁶ J/ψ events collected by BES detector at BEPC Collider.The branching ratios for three channels and the angular distribution for the first channel are measured.The branching ratios are Br(J/ψ→ΛΛ)=(l.08±0.06±0.24)×10^－3,Br(J/ψ→ΛΛγ)－4(90% CL)and Br(J/ψ→ΛΛπ⁰)=(2.3±0.7±0.8)×l0^－4 respectively. The angular distribution for J/ψ→ΛΛ is dN dcosθ=N₀(1+αcos²0),α=0.52±0.33±0.13.     

DISCUSSION OF A SU(2)×U(1)×S3 MODEL WITH TWO HIGGS DOUBLETS AND CALCULATION OF CABIBBO-LIKE-PARAMETERS

In this paper a SU(2)×U(1)×S₃ model with two Higgs doublets is discussed in detail. It is shown that besides the case discussed by Segre et al., there is another physically interesting case. We investigate the latter in detail. In This case, taking the quark masses and the Cabibbo angle θ₁ as input parameters, we can obtain Cabibbo angles θ₂ and θ₃ which have the same order of magnitude as θ₁. Finally the appearance of a pseudo Goldstone boson in the model is discussed, a method to overcome the difficulty is given, and the physical results of this case which do not contradict with the experiments are discussed.