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1.
The transverse vector vertex function in momentum space in four-dimensional QED is derived in terms of a set of transverse Ward-Takahashi relations for the vector and the axial-vector vertices in the case of massless fermion. It is demonstrated explicitly that the transverse vector vertex function derived this way to one-loop order leads to the same result as one obtained in perturbation theory. This provides a basic approach to determine the transverse part of basic vertex function from the symmetry relations of the system.  相似文献   

2.
The transverse Ward-Takahashi(W-T) realtion for the Vector vertex in quantum filed theory is derived by calculation the coul of the time-ordered product of the three-point function inclduing the vector current operator.This provides the constraint on the transverse part of the vertex.By combining the transverse and normal (longitudinal)W-T identities,we obtain the expression for the full vector vertex function.  相似文献   

3.
The transverse symmetry transformations associated with the normal symmetry transformations are proposed to build the transverse constraints on the basic vertices in gauge theories. I show that, while the BRST symmetry in non-Abelian gauge theory QCD (Quantum Chromodynamics) leads to the Slavnov-Taylor identity for the quark-gluon vertex which constrains the longitudinal part of thevertex, the transverse symmetry transformation associated with the BRST symmetry enables to derive the transverse Slavnov-Taylor identity for the quark-gluon vertex, which constrains the transverse part of the quark-gluon vertex from the gauge symmetry of QCD.  相似文献   

4.
We calculate the transverse Ward-Takahashi relation for the vector vertex in momentum space at one-loop order in four-dimensional Abelian gauge theory. We demonstrate explicitly that the result is exactly the same as that derived by using one-loop vector vertex calculations.  相似文献   

5.
We calculate the transverse Ward-Takahashi relation for the vector vertex in momentum space at one-loop order in four-dimensional Abelian gauge theory. We demonstrate explicitly that the result is exactly the same as that derived by using one-loop vector vertex calculations.  相似文献   

6.
Nonperturbative studies such as confinement and dynamical chiral symmetry breaking need the nonperturbative interacting vertex functions. In this paper, an approach to determining the full fermion-boson vertex function in four-dimensional Abelian gauge theory is presented: this full vertex function is derived in terms of a set of normal (longitudinal) and transverse Ward-Takahashi relations for the fermion-boson (vector) and axial-vector vertices in the momentum space in the case of massless fermion. Such a derived fermion-boson vertex function should be satisfied both perturbatively and nonperturbatively. The fact that such a derived full fermion-boson vertex function to one-loop order holds indeed is proven and the nonperturbative form of this vertex is also under discussion.  相似文献   

7.
We re-derive exactly the transverse Ward-Takahashi relation for the vector vertex in momentum space.The result shows that this transverse Ward-Takahashi relation in momentum space involves a perturbative correction term. We demonstrate explicitly that this transverse Ward-Takahashi relation is satisfied indeed at one-loop order.  相似文献   

8.
成泰民  鲜于泽 《物理学报》2006,55(9):4828-4836
在二维正方Heisenberg铁磁系统的基础上建立了磁振子-声子相互作用模型.利用Matsubara格林函数理论研究了系统的横向声频支声子激发,计算了布里渊区的主要对称点线上的横向声频支声子色散曲线,发现在第一布里渊区的Σ线上,小波矢区(Γ附近kxa<0.2)横向声频支声子有硬化现象,但是在软化区(0.25<kxa<0.7)有横向声频支声子有软化现象,在M附近(0.75<kxa)横向声频支声子有硬化现象.在Δ线上没有发生横向声频支声子有软化与硬化现象.在Z线上小波失区(X附近kxa<0.65)横向声频支声子有软化现象,但是在M附近横向声频支声子有硬化现象.并且又讨论了各项参数对横向声频支声子激发的影响,发现磁振子-声子耦合与自旋波劲度常数对横向声频支声子软化起很大的作用. 关键词: 磁振子-声子相互作用 横向声频支声子软化 Matsubara格林函数理论 铁磁系统  相似文献   

9.
We derive the transverse Ward-Takahashi identities(WTI) of N-dimensional quantum electrodynamics by means of the canonical quantization method and the path integration method, and subsequently attempt to prove that QED_3 is solvable based on the transverse and longitudinal WTI, indicating that the full vector and tensor vertices functions can be expressed in terms of the fermion propagators in QED_3. Further, we discuss the effect of different γ matrix representations on the full vertex function.  相似文献   

10.
刘新芽 《光学学报》1995,15(10):437-1440
推导了介质界面反射和折射电磁波的能量中心横向移动的计算式,它表明,横向移动的量值与入射波束的线度、入射角及介质的介电常数、磁导率有关。  相似文献   

11.
刘宝盈  李春芳 《中国物理 B》2008,17(10):3720-3724
This paper reports that the central position of the reflected and transmitted beams of a nonlinear polarized light beam at the interface between two media undergoes transverse shifts. It presents a solution to the problem of transverse shift of a non-uniformly polarized paraxial light beam transmitting through interfaces between two homogeneous media by using a two-form amplitude and an extension matrix to represent the vector angular spectrum of a three-dimensional (3D) light beam. It derives general formula for the transverse shift of the transmitted beam, and discusses the shift of a well-collimated beam transmitting through an interface between two homogeneous media and a thin dielectric slab.  相似文献   

12.
光传播路径横向风速风向的准确测量,对于科学研究和工程应用都具有重要意义。哈特曼传感器用来接收光波大气传输前向散射的波前和光强信息,提出利用哈特曼传感器接收的前向散射光强闪烁相关信息,实现路径横向风速廓线测量的方法。理论推导给出了光传播路径上横向风速分段反演的公式。根据不同的子孔径间距路径权重函数的差异,针对不同子孔径间距对路径不同位置的敏感性,分析了如何合理的选取光传播路径横向风速廓线的权重函数。利用哈特曼传感器开展了水平1 000 m光传输路径横向风速的探测实验。初步研究结果表明,哈特曼传感器测量的路径横向平均风速与接收端附近的风速计测量的结果具有较好的一致性;得到的两段路径横向风速的分布在随时间的变化趋势上一致性较好,特殊的下垫面布局使得靠近光源的第一段路径与靠近探测器的第二段路径的平均横向风速分别为1.273和0.952 m·s-1。将第二段横向风速与路径横向平均风速的测量结果进行了相关性分析,具有一致的变化趋势,两者的相关系数达0.86。  相似文献   

13.
将强子-核碰撞的独立源模型推广到核-核碰撞,给出了核-核碰撞末态产生粒子横能量分布方程,将其与CERN的NA35合作组得到的实验数据相比较,模型较好地解释了实验结果.  相似文献   

14.
HE  Han-Xin 《理论物理通讯》2009,(8):292-294
The transverse symmetry transformations associated with the normal symmetry transformations are proposed to build the transverse constraints on the basic vertices in gauge theories. I show that, while the BRST symmetry in non-Abelian gauge theory QCD (Quantum Chromodynamics) leads to the Slavnov-Taylor identity for the quark-gluon vertex which constrains the longitudinal part of the vertex, the transverse symmetry transformation associated with the BRST symmetry enables to derive the transverse Slavnov-Taylor identity for the quark-gluon vertex, which constrains the transverse part of the quark-gluon vertex from the gauge symmetry of QCD.  相似文献   

15.
张莉  罗海陆  文双春 《物理学报》2011,60(7):74207-074207
从平面角谱理论出发,建立了光束在空气和玻璃界面折射的传输模型.基于这一模型,揭示了光学马格努斯效应中的横向角移现象.对于特定的线偏振和椭圆偏振光束,其折射场重心出现了横向角移,而当入射光束为圆偏振时,横向角移则会消失.在正负折射率界面,光束的横向角移产生了反转现象,这是由于光束在左手材料中发生了负衍射.超高折射率可明显地减少横向角移,而超低折射率则可显著地增强横向角移.这些发现将为如何调控和增强光学马格努斯效应提供理论依据. 关键词: 光学马格努斯效应 横向角移 圆偏振  相似文献   

16.
The mean transverse velocity and elliptic flow of light fragments (A≤2) as a function of transverse radius are studied for 25 MeV/nucleon <'64>Cu+<'64>Cu collisions with impact parameters 3-5 fm by the isospin- dependent quantum molecular dynamics model. By comparison between the in-plane and the out-of-plane transverse velocities, the elliptic flow dependence on the transverse radius can be understood qualitatively, and variation of the direction of the resultant force on the fragments can be investigated qualitatively.  相似文献   

17.
The phase diagrams of a spin-2 transverse Ising model with a random field on honeycomb, square, and simple-cubic lattices, respectively, are investigated within the framework of an effective-field theory with correlations.We find the behavior of the tricritical point and the reentrant phenomenon for the system with any coordination number z, when the applied random field is bimodal. The behavior of the tricritical point is also examined as a function of applied transverse field. The reentrant phenomenon comes from the competition between the transverse field and the random field.  相似文献   

18.
较为全面地介绍了合肥光源横向模拟反馈系统研制过程中, 所涉及的部分关键问题, 如矢量运算模块的开发, Notch滤波器研制, 基于Hilbert变换进行相空间重建、模式分析, 反馈Kicker腔的研制.  相似文献   

19.
假定强子-核作用中的产生粒子相对于反应体质心系各向同性衰变,给出了强子-核作用中横能快度分布,计算结果能够解释最新的HELIOS合作组的实验结果.  相似文献   

20.
为了抑制BEPCⅡ产生的耦合束团不稳定性, 提高储存环中的流强, 研制了一套逐束团横向束流反馈系统的样机并在BEPC上做了实验, 得到了理想的结果. 当束团不稳定时, 频谱仪上可以观察到横向边带, 此时将反馈系统闭环工作于阻尼状态时, 横向边带立即消失. 本文介绍了样机系统的组成、各部分的功能和实验结果.  相似文献   

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