自旋为1/2的非Dirac粒子的电磁形状因子和极化

强子的电磁结构

Electromagnetic structure of hadrons

在以前的论文（/quant-ph/0204037，/quant-ph/0204134，quant-ph/0205075）中，我们从狄拉克方程出发，研究了轻子的电磁结构。本文利用杨-米尔斯方程分析强子的电磁结构。

Dirac-Foldy项与中子的电磁极化率

Dirac-Foldy term and the electromagnetic polarizability of the neutron

我们重新考虑了Dirac-Foldy对中子极化率的贡献$μ^2/m$。本文用狄拉克方程方法研究中子-核散射，回顾了康普顿连续谱极化率（$\barα$）、经典静态极化率（$α^n_E$）和薛定谔极化率（$α_{Sch}$）的定义，并详细讨论了它们之间的关系。后者$α_{Sch}$是使用薛定谔方程分析获得的中子电极化率值。我们特别发现了$α_{Sch} = \barα - μ^2/m$，其中$μ$是质量为$m$的中子的磁矩大小。然而，我们认为静态极化率$α^n_E$在粒子的静止坐标系中是正确定义的，从而得出结论：要得到静态极化率$α^n_E$，需要在$α_{Sch}$上加上两倍的Dirac-Foldy贡献。

Dirac equation for quasi-particles in graphene in an external electromagnetic field and chiral anomaly

There is evidence for existence of massless Dirac quasi-particles in graphene, which satisfy Dirac equation in (1+2) dimensions near the so called Dirac points which lie at the corners at the graphene's brilluoin zone. It is shown that parity operator in (1+2) dimensions play an interesting role and can be used for defining conserved chiral currents [there is no gamma^5 in (1+2) dimensions]. It is shown that the "anomalous" current induced by an external gauge field can be related to the anomalous divergence of an axial vector current which arises due to quantum radiative corrections provided …

介子电磁形状因子的分析性质对强子贡献对μ子$(g-2)$ -因子和介子电磁形状因子的限制

Restrictions on the Hadronic Contribution to the Muon $(g-2)$-factor and to the Pion Electromagnetic Formfactor from Analytical Properties of the Pion Electromagnetic Formfactor

本文从π介子形状因子的解析性质和类空区π介子形状因子的实验数据出发，研究了强子对μ介子$(g-2)$因子和π介子电磁形状因子贡献的限制条件。文[1]中的π介子形状因子的值得到了改进（见表1），并在另外20个点上计算了π介子形状因子的值（见表2）。

电磁狄拉克共生成

Electromagnetic Dirac Cogenesis

提出利用重矢量型费米子电磁偶极衰变至暗物质与轻狄拉克中微子右旋部分的共生成机制，同时生成重子与暗物质不对称性，预测DM质量约1 GeV，并可在伽马射线望远镜与CMB实验中探测。

Quantum diffusion of electromagnetic fields of ultrarelativistic spin-half particles

We compute electromagnetic fields created by a relativistic charged spin-half particle in empty space at distances comparable to the particle Compton wavelength. The particle is described as a wave packet evolving according to the Dirac equation. It produces the electromagnetic field that is essentially different from the Coulomb field due to the quantum diffusion effect.

Majorana versus Dirac Constraints on the Neutrino Dipole Moments

Massive neutrinos are guaranteed to have nonzero electromagnetic moments and, since there are at least three neutrino species, these dipole moments define a matrix. Here, we estimate the current upper bounds on all independent neutrino electromagnetic moments, concentrating on Earth-bound experiments and measurements with solar neutrinos, including the very recent results reported by XENONnT. We make no simplifying assumptions and compare the hypotheses that neutrinos are Majorana fermions or Dirac fermions. In particular, we fully explore constraints in the Dirac-neutrino parameter space. Maj…

不同位形电磁场中的中微子旋味振荡

Neutrino spin-flavor oscillations in electromagnetic fields of various configurations

本文研究了具有非零磁矩矩阵的混合Dirac中微子在不同组态的磁场中的自旋味振荡。我们讨论恒定的横向和扭转磁场。为了描述Dirac中微子的动力学行为，我们采用了基于Dirac-Pauli方程在外场中的精确解的相对论性量子力学方法。我们推导了不同中微子磁矩矩阵的跃迁几率。

Kinetic equations for massive Dirac fermions in electromagnetic field with non-Abelian Berry phase

We derive a semi-classical effective action and the kinetic equation for massive Dirac fermions in electromagnetic fields. The non-Abelian Berry phase structure emerges from two helicity states of massive fermions with positive energy. The classical spin emerges as a vector in SU(2) helicity space. The continuity equations for the fermion number and the classical spin are derived. The fermion number is conserved while the spin charge is not conserved by anomaly. Previous results about the coefficients of the chiral magnetic effect for the fermion and axial currents in the chiral limit can be r…

Exact solutions of the bound Dirac and Klein Gordon equations in non co propagating electromagnetic plane waves

A new class of exact solutions of the bound Dirac and bound Klein Gordon equations in non co propagating plane waves is found. The solutions are based on the physical principle of maintaining local gauge invariance in the Furry picture Lagrangian when N external fields can undergo independent gauge transformations. The solutions can be expressed in terms of the Hamilton Jacobi action and a gauge invariant effective particle momentum in the ensemble of external fields. Rotations of the effective particle momentum, which preserve local gauge invariance, are introduced into the action using matri…

Dirac方程表示的数学悖论

Mathematical Paradoxes of Dirac Equation Representations

本文研究了Dirac方程的两种表示形式，发现其在强电磁场下存在数学悖论，并通过仅使用正能量幅度状态来解决这些问题。

关于双质量态费米子的广义Dirac方程

On the Generalized Dirac Equation for Fermions with Two Mass States

分析了描述自旋为1/2的双质量态粒子的广义二阶Dirac方程。得到了提取具有确定能量和自旋投影态的投影算符。导出了20维矩阵形式的一阶广义Dirac方程和相对论不变的双线性形式。得到了用20分量波函数表示的电磁流的正则能量动量张量和密度。考虑了费米子的最小和非最小电磁相互作用，得到了量子力学的哈密顿量，并证明了在所考虑的方法中只有因果波的传播.

次领头阶QCD预测Σ狄拉克形式因子

Next-to-Leading-Order QCD Predictions for the $Σ$ Dirac Form Factors

本文基于QCD修正计算，结合硬核与非微扰分布幅度，提出Σ超子电磁形式因子的最新理论预测。