规范作用与引力的统一

在标准模型手征扩充理论的基础上,假定规范作用与引力统一,计算表明,夸克和轻子只可能有三代;所定出的统一点的能量标度为4.4×10¹⁸GeV轻子性夸克的质量标度为10¹⁰GeV.     

e+e－湮灭与大横动量P⊥分布

本文从e⁺e^－湮灭的次级粒子的横动量分布的表示式中, 导出了当m_⊥>>T时横质量m_⊥的平均无标度性.     

袋模型中强子结构函数的雷吉修正与标度破坏

本文利用文献[1]给出的方法计算了介子结构函数. 在另级近似下对于π介子有: W^π₁(x)~(1-x). 接着引入共振-雷吉修正的近似式, 得到在整个区间0≤x≤1与实验相符的核子、π介子价夸克分布函数. 我们还推测了标度破坏对旁观夸克数及有效袋半径的可能影响. 最后指出海夸克的分布函数也可用相似的玻密修正估算.     

对带电轻子质量公式的一些猜测

本文建议轻子电磁自能通过（（δm）/m）=（1/（2π））n^-b 与量子数 n 联系起来,其中 b 为待定常数.并建议动量截断值 M 与引力常数 k 和精细结构常数α的联系为 M=（?）.得到了带电轻子质量公式（?）.利用 e^-和μ^-质量的实验值和α值作输入,给出计算值 k=（6.67231±0.00026）×10^-8 cm³g^-lsec^-2和m_τ=（1782.306±0.078）MeV,与观察值 k=（6.6720±0.0041）×10^-8cm³ g^-1sec^-2和 m_τ=(1782_-4⁺³)MeV 很好符合.公式预言第四个带电轻子质量应为 m=（11725.47±0.51）MeV 可以在最近的实验中检验。本文还对所建议的质量公式和结果进行了讨论.     

密度矩阵对π－核光学位中泡利修正项的影响

π^－核光学位中的泡利修正项与密度矩阵密切相关. 本文分别用均匀费米气体模型、定域费米气体模型、修正的定域费米气体模型和壳模型谐振子波函数计算了O¹⁸的密度矩阵, 并由此研究了在Δ₃₃共振区(π分子动能为50～300MeV的区域)二级π^－核光学位中的泡利修正项. 对四种情况进行了分析、比较.     

Fep(x, Q2-Fen(x, Q2)的行为和标度性破坏参数

利用在文章[1]中给出的强子的价夸克分布函数的解析表达式, 我们讨论了电生过程的非单态分量, F^ep-F^en, 标度性破坏参数F^ep(x, Q²), 以及一些其它的量. 文中也给出了与实验数据的比较.     

壳效应对深部非弹性碰撞的影响

在高于相互作用位垒30%的能量下, 对对称系统¹⁵⁴Sm+¹⁵⁴Sm和¹⁴⁴Sm+¹⁴⁴Sm进行了运动学上的完全测量. 选择这两个系统是因为它们具有不同的内部结构: ¹⁴⁴Sm有N=82的中子闭壳层, 属球形基态构型; ¹⁵⁴Sm则在这个壳层外还有10个中子, 是强形变核. 在全部动能损失范围内, 所测得的两个反应的质量分布宽度是相近的, 但在能量损失小时, ¹⁴⁴Sm系统的电荷分布宽度要大得多. 基于壳修正的势能面计算, 可知这是由于N=82闭壳层影响所致, 在¹⁴⁴Sm系统中, 它阻碍了中子交换, 使得质子转移占优势.     

√s=540GeV pp碰撞中KNO无标度性研究

本文运用多火球独立产生模型^[1]计算了√s=540GeV pp碰撞中的KNO无标度性曲线和多次矩. 理论计算结果与实验结果符合得很好, 并揭示了其物理背景.     

裂变质量分布的非平衡统计理论

本文把Ayik等人关于重离子核反应的非平衡统计理论运用于核裂变过程,证明了冯氏裂变统计理论是Fokker-Planck方程的稳定解情形,平衡时质量分布的峰值位于位能曲面的极小值处。本文还通过用Suzuki标度极限近似法解一个简化的数学模型,表明裂变过程中核子输运趋向平衡的时间约为10^-21秒的数量级,估计出²³⁵U（n,f）从鞍点到断点的时间应大于1.6×10^-21秒。     

光生相对论的（μ+μ-）,（e+e-）仲原子

本文应用复合场论微扰展开式和相对论的 B-S 近似波函数,计算了类似于 Primakoff 效应的光生相对论的（e⁺e^-）,（μ⁺μ^-）仲原子的过程.结果与通常点模型的计算结果不同,这里多得出了一个新的形状因子.这表明在通常的Primakoff 效应中也将存在类似的修正.     

Unifying Gauge Interaction and Gravity in Vector-Like Standard Model

A supersymmetric vector-like standard model without leptons is suggested to investigate the unification between gauge interactions and gravity under two loop approximation for gauge interactions and one loop string correction for gravitation. It is found that two intermediate mass scales are needed where the lower mass scale may be accessible in laboratory in future and the higher mass scale is of the order of 10¹⁶GeV.     

Two loop electroweak corrections from heavy fermions to b→s+γ

Applying an effective Lagrangian method and an on-shell scheme, we analyze the electroweak corrections to the rare decay b→, s+γ from some special two loop diagrams in which a closed heavy fermion loop is attached to the virtual charged gauge bosons or Higgs. At the decoupling limit where the virtual fermions in the inner loop are much heavier than the electroweak scale, we verify the final results satisfying the decoupling theorem explicitly when the interactions among Higgs and heavy fermions do not contain the nondecoupling couplings. Adopting the universal assumptions on the relevant couplings and mass spectrum of new physics, we find that the relative corrections from those two loop diagrams to the SM theoretical prediction on the branching ratio of B → Xsγ can reach 5% as the energy scale of new physics ANp=200 GeV.     

Loop variables and gauge invariant exact renormalization group equations for (open) string theory

An exact renormalization group equation is written down for the world sheet theory describing the bosonic open string in general backgrounds. Loop variable techniques are used to make the equation gauge invariant. This is worked out explicitly up to level 3. The equation is quadratic in the fields and can be viewed as a proposal for a string field theory equation. As in the earlier loop variable approach, the theory has one extra space dimension and mass is obtained by dimensional reduction. Being based on the sigma model RG, it is background independent. It is intriguing that in contrast to BRST string field theory, the gauge transformations are not modified by the interactions up to the level calculated. The interactions can be written in terms of gauge invariant field strengths for the massive higher spin fields and the non-zero mass is essential for this. This is reminiscent of Abelian Born–Infeld action (along with derivative corrections) for the massless vector field, which is also written in terms of the field strength.     

Dispersion-theoretic calculation of the lepton magnetic moment and form factors in the gauge theory of weak interactions

We have evaluated, by dispersion-theoretic techniques, the form factors and the magnetic moment of leptons, taking into account the new particles introduced in the gauge theory of weak interactions. In these calculations all particles are on the mass shell, and only particles contributing to the unitarity condition need to be considered. The calculations are unambiguous and there is no problem of choice of the loop variable. The relation of the gauge and the corresponding additional particles in the unitarity is discussed.     

Higher dimensional operator corrections to the goldstino Goldberger–Treiman vertices

The goldstino–matter interactions given by the Goldberger–Treiman relations can receive higher dimensional operator corrections of , where M denotes the mass of the mediators through which SUSY breaking is transmitted. These corrections in the gauge mediated SUSY breaking models arise from loop diagrams, and an explicit calculation of such corrections is presented. It is emphasized that the Goldberger–Treiman vertices are valid only below the mediator scale, and at higher energies goldstinos decouple from the MSSM fields. The implication of this fact for gravitino cosmology in GMSB models is mentioned. Received: 22 December 1998 / Revised version: 1 July 1999 / Published online: 17 February 2000     

Determination of the Glueball Mass Spectrum with the Spin-Orbit Interaction

Based on the investigation of the asymptotic behaviour of the polarization loop function for scalar charged particles in an external gauge field we determine the interaction Hamiltonian including the nonperturbative corrections of the relativistic character of motion and the large coupling constant. The mass spectrum of the bound state is analytically derived. The mechanism for arising of the constituent mass of the bound-state forming particles is explained. The change of the bound-state mass and of the constituent mass of particles is analyzed by varying the coupling constant. The mass spectrum of the two-gluon glueball is calculated taking into account spin-orbit and spin-spin interactions.     

New formulas and predictions for running masses at higher scales in MSSM

The effects of the scale dependent vacuum expectation values (VEVs) on the running masses of quarks and leptons in non-SUSY gauge theories have been considered by a number of authors. Here we use RGEs of the VEVs, and the gauge and Yukawa couplings in the MSSM to analytically derive new one loop formulas for the running masses above the SUSY breaking scale. Some of the masses exhibit a substantially different behaviour with respect to their dependence on the gauge and Yukawa couplings when compared with earlier formulas in the MSSM derived ignoring RGEs of VEVs. In particular, the masses of the first two generations are found to be independent of the Yukawa couplings of the third generation in the small mixing limit. New numerical estimates at the two loop level are also presented. Received: 30 July 1999 / Published online: 6 April 2000     

Dirac neutrino masses from generalized supersymmetry breaking

We demonstrate that Dirac neutrino masses in the experimentally preferred range are generated within supersymmetric gauge extensions of the standard model with a generalized supersymmetry breaking sector. If the superpotential neutrino Yukawa terms are forbidden by the gauge symmetry [such as a U(1)'], sub-eV scale effective Dirac mass terms can arise at tree level from hard supersymmetry breaking Yukawa couplings, or at one loop due to nonanalytic soft supersymmetry breaking trilinear scalar couplings. The radiative neutrino magnetic and electric dipole moments vanish at one-loop order.     

格点规范理论(Ⅰ)

本文介绍了由Wilson等人发展起来的处理粒子间强相互作用的格点规范理论。由于这个理论是建立在点阵上的规范理论,故首先讨论了点阵上体系的场论性质和统计物理性质之间的联系,介绍了处理粒子禁闭问题的Wilson判据,点阵的哈密顿形式。然后讨论了各种具体模型的计算方法,如规范场的点阵模型、紧致QED模型、费米子模型、阿贝尔Higgs模型等。在此基础上,总结出Wilson定理。本文也讨论了格点规范理论中的实空间重正化群方法,介绍了Heisenberg平面模型的重正化群分析,一维的二维的复现关系及Migdal近似。最后评介了近年来对于Wilson回路算子的一些研究,内容包括’t Hooft代数和Wilson回路算子方程等。     

Light singlet particles and their cosmological consequences in witten-type supersymmetric models

In a class of supersymmetric gauge models which generate a large mass scale from a supersymmetry breaking mass scale M through loop corrections, there exists generally a very light scalar particle which transforms like a singlet under SU(3)_c × SU(2)_L with no U(1) charge. Cosmological constraints on such a particle are so severe that an upper bound is set on possible values of supersymmetry breaking scale in this class of models as M ? 500 TeV provided that the large mass scale is 10¹⁵ GeV and the mass of the light scalar particle is generated in one-loop order. This bound holds even if the goldstino is not absorbed into the gravitino.