论文标题
中立Lepton过渡偶极时刻中的CP违规
CP violation in neutral lepton transition dipole moment
论文作者
论文摘要
中微子过渡电磁偶极矩的$ cp $违规在标准模型的背景下，使用任意数量的右手单元中微子进行了讨论。在Feynman仪表中进行了中微子电磁形式因子的完整一环计算。非零$ cp $不对称是由中微子群体所需的阈值条件以及违反Lepton风味混合矩阵中的非变化$ cp $违反阶段而产生的。我们遵循中微子振荡的$ cp $违规行为，将风味混合的贡献参数分为一系列类似Jarlskog的参数。然后将这种形式主义应用于最小的Seesaw型号，其中两个重型右手中微子表示$ N_1 $和$ N_2 $。我们观察到，腐烂到光中微子$ n \至νγ$的$ cp $ symmetries受到极大抑制，最大左右$ 10^{ - 17} $。但是，$ cp $不对称$ n_2 \至n_1γ$可以达到订单统一。即使Dirac $ cp $ phase $δ$是$ cp $违规的唯一来源，大约$ cp $不对称的$ 10^{ - 5} $ - $ 10^{ - 3} $是舒适的。
The $CP$ violation in the neutrino transition electromagnetic dipole moment is discussed in the context of the Standard Model with an arbitrary number of right-handed singlet neutrinos. A full one-loop calculation of the neutrino electromagnetic form factors is performed in the Feynman gauge. A non-zero $CP$ asymmetry is generated by a required threshold condition for the neutrino masses along with non-vanishing $CP$ violating phases in the lepton flavour mixing matrix. We follow the paradiagm of $CP$ violation in neutrino oscillations to parametrise the flavour mixing contribution into a series of Jarlskog-like parameters. This formalism is then applied to a minimal seesaw model with two heavy right-handed neutrinos denoted $N_1$ and $N_2$. We observe that the $CP$ asymmetries for decays into light neutrinos $N\to νγ$ are extremely suppressed, maximally around $10^{-17}$. However the $CP$ asymmetry for $N_2 \to N_1 γ$ can reach of order unity. Even if the Dirac $CP$ phase $δ$ is the only source of $CP$ violation, a large $CP$ asymmetry around $10^{-5}$-$10^{-3}$ is comfortably achieved.
