PRELIMINARY TEST FOR AGEING EFFECT OF DRIFT CHAMBERS

The degradation of some performances of the drift chambers irradiated with 5 MeV electron beam has been tested. The gas mixtures filled were Ar/CO₂, Ar/CH₄ and C₄H₁₀ in proportion.
The dark current, the pulse height, the energy resolution and the counting rate plateau have been measured during the irradiation.     

PERFORMANCE OF THE PARALLEL MULTIPLATE AVALANCHE CALORIMETER

This is the first try to use PPAC as sampling calorimeter. The article is discussing the possible fluctuations in this type of calorimeter, presenting the results of simulating measurements performed on single gap PPAC and actual measurements for multiplate PPAC calorimeter. It is prospected that the energy resolution could be 17%/√E, if using 2 mm Pb plates as absorbers.     

THE EFFECTS OF THE CHARM STATE IN e-p DEEP INELASTIC SCATTERING

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 R=σ_L/σ_T in e-p deep inelastic scattering with the experimental data is obtained.     

THE BEHAVIOR OF THE PHASE-SHIFT IN THE BAKAMJIAN-THOMAS THEORY

The behavior of the phase-shift of the Bakamjian-Thomas theory and its relationwith the phenomenological nuclear force V=V_RiV_I 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.     

ON THE IRREDUCIBLE REPRESENTATIONS OF THE COMPACT SIMPLE LIE GROUPS OF RANK 2(III)

In this paper, using the method employed in two earlier papers: "On the Irredu-cible Representations of the Compact Simple Lie Groups of Rank 2(I) and (II)",theirreducible representations of the groups B₂ and G₂ are discussed. A method for cal-culating the irreducible representations of these groups is given. Moreover,some ofthe low dimensional representations of these groups are calculated.     

INCREASE OF BEAM PROJECTIVE EMITTANCE IN SYSTEM WITH DISPERSION

In this paper, the increase of beam projective emittance caused by the momentum dispersion in the transport systems is discussed, and the incrementary ratio is derived. If the bending plane is (XOZ), the incrementary ratio of the transversal emittance is

and the longitudinal one is

Here ε_x0 and ε_z0 are original emittances in the x-direction and z-direction respectively, (Δp/p)_maxis beam momentum spread β_xf, α_xf, γ_xf being acceptance parameters of the system in x-direction for betatron oscillations, η and η' are dispersion function and its derivative.     

INTRODUCTION OF THE CONCEPT OF THE DEPAIRING PROBABILITY TO EXPLORE NUCLEAR HIGH SPIN STATES

In order to explore nuclear high spin states,a physical concept of depairingprobability has been suggested,which is based on the CAP and the RAL effects inthe nuclear rotating system.We think that the depairing process,might be gradualat begin—then dramatic and finally gradual again.According to the concept ofthe depairing probability and the particle-rotor model,a formula for the spectrum ofrotational energy has been obtained,and the spectra for more than fifty nuclei have been calculated by using this for-mula.The calculated results are found to be in reasonable agreement with experi-mental data,and are able to reproduce the experimentally observed various backbending phenomena on the plots of g_eff—ω_eff².     

TRACELESS OPERATORS AND SO6 WAVE FUNCTIONS OF sd BOSONS

Traceless operators of sd bosons are introduced and used to construct the SU₆SO₆SO₅SO₃ wave functions of sd bosons according to the method of T.S.Yang     

FURTHER DISCUSSION ON THE EQUATION AND ITS SOLUTIONS FOR THE BOUND STATES OF MESONS

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 V_D（r） corresponding to the potential V_v（r） in our previous work, the calculated radii of the bound mesons do approach the experimental value.     

THE BEHAVIOURS OF F2ep(X,Q2)-F2en(X,Q2) AND THE SCALE-BREAKING PARAMETER

The scale-breaking parameter F₂^ep(x, Q²) of non-singlet component F₂^ep-F₂^en 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.

     

ANALYSIS OF HADRONIC EVENTS

In this paper I summarize some results obtained from analyses of hadronic final state events. The analyzed data sample comes from Mark-J collaboration and covers an energy range from √S=12GeV to √S =46.78GeV. The integrated luminosity is 128.06Pb^－1. We can search for production of open top quarks and toponium by measuring the total hadronic crossection R =3.85±0.02±0.12 was measured in the above mentioned energy range. It is consistent with R≈3.9 as expected from QCD for five different quark flavors. We search for the narrow bound states of the toponium from 39.79GeV to 46.78GeV. The most prominent resonance signal is at a c.m. energy √S=45.12±0.04GeV and results in an upper limit of B_h.Γ_ee≤3.00keV(95% C.L.).     

QCD PREDICTION FOR THE REACTION γ+p→2γ+X

In the framework of the perturbative QCD, the two-fold differential cross section d²σ/dx_Tdx_L of the reaction γ+p→2γ+X and its two backgrounds (γ+p→γ++X, γ+p→γ++X) are calculated in c.m.s.. The results show that, in a large range of (x_T, x_L), the calculated reaction cross section can be measured in current laboratory condition. And due to the properties of this reaction, i.e., large p_T photoproduction and direct photon pair emission, all of the backgrounds can be greatly suppressed.

     

APPROXIMATE B.S. WAVE FUNCTIONS FOR AN ELECTROMAGNETIC BOUND SYSTEM OF SPINS (1/2, 1/2) OR (1/2, 1/2) WITH UNEQUAL MASSES

The Bethe-Salpeter equation for an electromagnetic bound system of spins (1/2—1/2) or (1/2—1/2) with unequal masses are solved in this paper. The approximate B.S. wave functions for these systems are given. Utilising these wave functions, the decay rate and branching ratio for Ξ⁰→(Σ⁺μ^－)+v_μ are calculated with accuracy up to order O(α). The results are wΞ⁰→(Σ⁺μ^－)+v_μ1.12(1/sec) and R=[wΞ⁰→(Σ⁺μ^－)+v_μ]/[wΞ⁰→(Σ⁺μ^－)+v_μ]4.7×10^-7. Similarly, the process Λ→(pμ^－)+v_μ is also discussed.     

B → A transitions in the light-cone QCD sum rules with the chiral current

In this article, we calculate the form-factors of the transitions B → a₁(1260), b₁(1235) in the leading-order approximation using the light-cone QCD sum rules. In calculations, we choose the chiral current to interpolate the B-meson, which has the outstanding advantage that the twist-3 light-cone distribution amplitudes of the axial-vector mesons makes no contributions, and the resulting sum rules for the form-factors suffer from far fewer uncertainties. Then we study the semi-leptonic decays B → a₁(1260) lv_l, b₁(1235) lv_l (l=e,μ,τ), and make predictions for the differential decay widths and decay widths, which can be compared with the experimental data in the coming future.     

THE TEST OF SLAC METHOD USING LEE MODEL

Treating Lee Model by Slac method,we find that,to state ||V> of one particle and state ||VN> of two particles,there corresponds a solution of Slac bag type re-spectively.The latter bears resemblance to the former in energy especially for ||V> state with the replacement of the interaction constants g by g/√e only.In addition,the“bag”corresponds precisely to the scalar field in ||V> and ||VN> states.However,for ψ_N^- and ψ_V^- field,we get δ-function type solutions by Slac method.They deviate greatly from the rigorous solutions.The“skin confinement”as statedby Bardeen et al.,and Rafelski is closely related to the δ-confinment in the one par-tiele state found here by coherent state approximation.Thus it may not representthe physical picture in the rigorous solution of a quantum field theory.     

SOME CONJECTURES ON THE MASS FORMULA OF CHARGED LEPTONS

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/√κ）αe^-1-b.So we obtainthe mass formula of charged leptons M=（1/√κ）α 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 m_r=（1782.306±0.078）MeVwhich agree very well with experimental values κ=（6.6720±0.0041）×10^-8cm³g^-1sec^-2 and m_τ=(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.     

TESTING GLUON DISTRIBUTION FUNCTION OF HADRONS IN LARGE PT PROCESS WITH DIRECT PHOTON EMISSION

In this paper we disscuse disscuse the physicsical aspect of cross-section differences Δ_AB^cγ=dσ(AB→cγX)-dσ(AB→cγX) and give the simple rules to select the elementary subprocesses which contribute to cross-section differences.
We bind a way to test the gluon distribution functions of hadrons through the measurement of cross-section difference or combination of cross-section differences in the large P_T process with direct photon emission. Moreover we obtain simple relations between each combination of cross-sections and the corresponding gluon distribution functions of proton, neutron, pion and daon:
G_p⁸(x)/(Δ_pp^hγ－Δ_pp^hγ)=G_n⁸(x)/(Δ_pp^hγ)=G_π⁸(x)/(Δ_π+p^hγ+Δ_π－p^hγ=G_K⁸(x)/(Δ_K+p^hγ+Δ_K－p^hγ)which are expected to be test in experiment.     

The Production of Bc(Bc) Meson Through Z0 Boson Decay

Based on the most important "hard" production mechanism,the production rate of B_c(or B_c) meson being accompanied with one c(or c) and one b(or b) heavy quark jets through Z⁰ decay is computed in this paper.It is pointed out that at LEP up to next run,quite a lot of events with one B_c or B_c meson may be obtained,so that it becomes accessible to study the properties of B_c and B_c mesons throngh Z⁰ decay experimentally.     

THE CLASSIFICATION OF THE WAVE FUNCTIONS OF BOSONS AND FERMIONS

In this paper we have proved that the wave functions for bosons and fermionscan be classified by either of the following two Lie superalgebra chains U(2l+1/2j+1) SU(2l+1/2j+1) SU(2l+1)SU(2j+1) SO(2l+1)Sp(2j+1) SO(3)SO(3), U(2l+1/2j+1) SU(2l+1/2j+1) OSp(2l+1/2j+1) SO(2l+1)Sp(2j+1) SO(3)SO(3) The wave functions for bosons and fermions classified by the Lie superalgebra chain U(2l+1/2j+1) SU(2l+1/2j+1) SU(2l+1)SU(2j+1) SO(2l+1)Sp(2j+1) SO(3)SO(3), are calculated also.     

Searches for the technicolor signatures via gg → W±πt± at the Large Hadron Collider

In this paper, we calculate the production of a charged top pion in association with a W boson via gg fusion at CERN's Large Hadron Collider in the context of the topcolor assisted technicolor model. We find that the total cross section of pp → gg → W^±π_t is several dozen femtobarns with reasonable values of the parameters, and the total cross section of pp → W^±π_t can reach a few hundred femtobarns when we consider the sum of the contributions of these two parton subprocesses, gg → W^±π_t and bb → W^±π_t.