The Fractional Parentage Coefficients for a Double-j Fermion System

The coefficients of fractional parentage (CFPs) for a double-j fermion system are defined. The CFPs are given when the wave functions are classified according to the group chains U(N) ⊃ U(N₁) × U(N₂) ⊃ SP(N₁)× SP(N₂) ⊃O(3₁)×O(3₂) ⊃ O(3) and U(N) ⊃ SP(N) ⊃ SP(N₁)× SP(N₂) ⊃ O(3₁)× O(3₂) ⊃ O(3). Using these CFPs many repeating calculations can be avoided.     

The Branching Rules for SU(2N)⊃(SU(N)⊃O(N)⊃O(3))⊗SU(2) and the Highest Weight States for SU(N) and O(N)

Simple analytical recurrent formulae of the branching rules for group chain SU(2N)⊃(SU(N)⊃O(N)⊃O(3))⊗SU(2) are obtained. The highest weight states for the irreducible representations [2^al^b] or {nS} of group SU(N) and for the irreducible representations (2^α1^β) or (υS) of group O(N) are constructed respectively     

Irreducible Representations and Reduced Coefficients of Quantum Algebra SUq(4) in the SUq(4)⊃ SUq(2)⊕SUq(2) Basis

In this paper, the tensor-like method is presented, and the applications to quantum algebra SU_q(4) are given. The irreducible representation of SU_q(4) and a recurrent formula to calculate reduced coefficients of SU_q(4)⊃ SU_q(2)⊕SU_q(2) is obtained. Some of reduced matrix elements and q-reduced scalar factors (qRF) are tabulated.     

HYPERSPHERICAL FUNCTION AND SP(2,R)GROUP

In the present paper a method for constructing the hyperspherical function for the internal motion of many-body system in the scheme Sp(2m,R)⊃Sp(2,R)×O(m) based on the complementarity of the symplectic Sp(2,R) and the orthogonal O(m) groups is developed. A generate formula for the fractional-parentage coefficients of the hyperspherical function is obtained and it is shown that the formula can be used to to calculate the spectroscopic factor for the arbitrarym-cluster,etc..     

INFINITE DIMENSIONAL EOSON-FERMION REPRESENTATIONS OF LIE SUPERALGEBRAS D(M,N)

The Lie superalgebras D(M,N) are realized by creation and annihilation operators of bosons and fermions. The infinite-dimensional IR(irreducib1e representations) are constructed. These IR are star representations. And the IR are decomposed according to the superalgebra chain D(M,N)⊃A(M-1, N-1).     

A Recurrent Formula for Fractional Parentage Coefficients of Identical Fesmions

A recurrent formula of fractional parentage coefficients (CFPs) with explicit senioritiea for identical fermions in the j-j coupling acheme is given. The multiplicity of statee with fixed seniority and angular momentum is also given. Using irreducible tensor method, the CFPs are factorized completely along a group chain. It is found that the CFPs are directly related to the group reduction coefficients. Them are useful for constructing an efacient iteration method of calculating the CFPs.     

Reduction Factors for O(N)⊃O(NK-1)

In terms of the concept of irreducible tensor basis and the properties of irreducible tensor operator, we give, by mathematical induction, the irreducible representations of O(N) for (m_1Nm_2N...m_[N/2]N) and all reduction factors of O(N)⊃O(N-1) for (1 0...0)⊗(m_1Nm_2N...m_[N/2]N)     

The Branching Rules for U(7)⊃0(7)⊃G2⊃0(3)

The branching rules for U(7)⊃0(7)⊃G₂ and G₂⊃0(3) for at most fourcolumned IRs of U(7)) and O(7) are given respectively by using the method of decomposition of Kronecker products of IRs of groups. The needed formulae for decomposition of Kronecker products of IRs of O(7) and G₂ are given also.     

Coupling Coefficients of Quasispin Group SO(5)t

A recurrent method for coupling coefficient calculations of five-dimensional quasispin group SO(5)_t is proposed. The explicit coupling coefficients such a .     

On the Boson Representations of SU(3) Algebra in the Basis SU(3)⊃U(1)+U(1)

The Dyson and Holstein-Primakoff boson realizations of the generators of SU(3) algebra have been given for the algebra chain SU(3)⊃U(1)+U(1), and a set of recursion formulae of the transformation matrix, which turn the Dyson onto the Holstein-. Primakoff representation, have been presented. The multiplicity that can occur in the reduction of SU(3)⊃U(1)+U(1) is naturally determined.     

U（N）SP（N）O（3）的分支律

利用群的直乘分解公式，考虑Ｕ（Ｎ）群的［２ａ１ｂ］表示按群链Ｕ（Ｎ）ＳＰ（Ｎ）Ｏ（３）的约化规则，给出了相应的比较简单的分支律递推公式．该公式在用计算机计算分支律时，不受秩和表示维数的限制．为求解这类问题的分支律提供了一种比较简单的算法．在简化同位旋１／２的单ｊ费米子体系的母分系数计算中具有十分重要的意义．用同样的方法也可以求出群链Ｕ（Ｎ）Ｏ（Ｎ）Ｏ（３）的分支律．     

Three-Generat ion Models from Global Gauge Anomaly-Free Theories

In this work, we show how a global gauge anomaly of a gauge group H can be computed from a local one of a larger gauge group G ⊃ H. We also show that the number f of generations is tied to the consistency of a gauge theory H with initially a Z_f gIobal gauge anomaly. We give some examples of SU(N) models, in different dimensions of spacetime, with three families.     

DYNKIN'S EMBEDDING METHOD AND SUBALGEBRA CHAINS OF U(6)⊃SU(3)*

Use Dynkin's embedding method to find out the generators of two subalgebra chains of U(6)⊃SU(3).     

单模双包层光纤之间的耦合

本文求得了单模双包层光纤之间耦合系数精确的解析表达式.计算了上升内包层、匹配包层和凹陷内包层光纤耦合系数随归一化频率V的关系曲线.也给出了不同V值的耦合系数随归一化距离(D/α)的关系曲线.该公式不但能够计算x偏振模的耦合系数,而且也能计算y偏振模的耦合系数.它可用于分析折射率差较大的光纤之间能量耦合以及耦合器的偏振特性.     

The F-Spin Formalism of the Neutron-Proton Interacting Boson Model

The neutron-proton interacting boson model is presented in the F-spin formalism. Hamiltonian and transition operators are rewrit ten in the F-spin formalism based on group chain U(12)⊃U(6)⊗SU_F(2). Matrix elements are given explicitly in terms of the cfp's with F-spin. Different forms of Hamiltonian in IBM-2 are compared, and their relations are given.     

Mass and KLamda coupling of the N*(1535)

Using a resonance isobar model and an effective Lagrangian approach, from recent BES results on J/psi-->ppeta and psi-->pK+Lamda, we deduce the ratio between effective coupling constants of N*(1535) to KLamda and peta to be R=gN*(153)KLamda/gN*(1535)peta=1.3+/-0.3. With the previous known value of gN*(1535)peta, the obtained new value of gN*(1535)KLamda is shown to reproduce recent pp-->pK+Lamdanear-threshold cross section data as well. Taking into account this large N*KLamda coupling in the coupled channel Breit-Wigner formula for the N*(1535), its Breit-Wigner mass is found to be around 1400 MeV, much smaller than the previous value of about 1535 MeV obtained without including its coupling to KLamda. The implication on the nature of N*(1535) is discussed.     

Higher order contributions in finite temperature renormalization group

We apply to the O(N) λφ⁴ model the finite temperature renormalization group method, in which the temperature-dependent effective coupling constant and mass are introduced. It is pointed out that the improvement by use of the two-loop renormalization-group coefficients is important at high temperature and drastically changes the lowest order result. We also show that the two-loop renormalization-group coefficients are exact in the large-N limit.     

Collision strengths for the N = 2 excitation of hydrogenic ions

An empirical formula is given for the estimation of the collision strengths for electron impact excitation of the 2s and 2p states of hydrogenic systems based on close coupling calculations. The coefficients in this formula are given as functions of the nuclear charge, Z, thereby making a possible estimation of the collision strength for any system between H and Fe²⁵⁺.     

On the generation of operator equivalents and the calculation of their matrix elements.

To find all components T((k))(+/-q) = N(k,q)J(q)(+/-) summation operator(k-q)(m=0) (+/-1)(k-m)a(k, q; m)J(m)(z) (0 相似文献   

Simulation of electromechanical coupling coefficient by modified modal frequency spectrum method including the electrode effect

An approximate formula has been developed to determine the electromechanical coupling coefficient of the piezoelectric film in a four-layer composite resonator, which includes two electrodes. In this formula, the coupling coefficient can be calculated from the distribution of the effective coupling coefficients, k2eff, which are given by the modal frequency spectrum of the composite resonator. The feasibility of this method has been demonstrated with a ZnO/SiO2 composite resonator for different electrode thickness. The effect of mechanical propagation loss in both piezoelectric layer and substrate has also been studied.