arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1601.04788hep-phhep-ex
收藏

具有剩余$Z_3$对称性的轻Flavon的质量极限

Mass Limit for Light Flavon with Residual $Z_3$ Symmetry

Yu Muramatsu, Takaaki Nomura, Yusuke Shimizu

摘要:

我们提出了一个改进的Altarelli和Feruglio $A_4$模型,其中引入了一个额外的$A_4$单线素黄酮。在这个模型中,非零的$θ_{13}$由这个额外的$A_4$单重素flavon给出,它打破了三重双峰混合。在具有$U(1)_R$对称性的超对称性框架下,我们通过驱动场得到了黄子的真空期望值和真空期望值排列。研究认为,当黄酮质量较轻时,黄酮会引起独特的风味破坏过程。假设超对称粒子的质量足够大,使得超对称贡献可以忽略不计,我们讨论了在带电轻子扇区中通过flavon交换的味道破坏Yukawa相互作用。根据势分析,在带电轻子扇区中,黄子的VEV将$A_4$分解为$Z_3$,并确定了黄子质量之间的关系。由于剩余的$Z_3$对称性,除了$τ\rightarrow μμ\bar{e}$和$τ\rightarrow e e \barμ$,许多轻子味违反衰变模式被禁止。考虑到Belle实验目前的实验下限,来自这些三体衰变模式的黄酮的质量极限为$60$ ~GeV。在我们的模型中,我们通过使用已知的带电轻子质量预测分支比$τ\rightarrow μμ\bar{e}$和$τ\rightarrow e e \barμ$的比率。我们还发现黄酮的生成截面可以是$\mathcal{O}(1)$ fb。因此,通过寻找4-τ轻子信号,可以在LHC运行2中找到黄酮。

英文摘要:

We present a modified Altarelli and Feruglio $A_4$ model where an additional $A_4$ singlet-prime flavon is introduced. In this model, non-zero $θ_{13}$ is given by this additional $A_4$ singlet-prime flavon which breaks tri-bimaximal mixing. In the framework of the supersymmetry with $U(1)_R$ symmetry, we obtain vacuum expectation values (VEVs) and VEV alignments of flavons through driving fields. It is considered that flavon induces distinctive flavor violating process if flavon mass is light. Assuming mass of SUSY particles are sufficiently heavy so that the SUSY contributions can be negligible, we discuss the flavor violating Yukawa interaction through flavon exchange in the charged lepton sector. According to the potential analysis, the VEV of flavon breaks $A_4$ down to $Z_3$ in the charged lepton sector and relation among flavon masses is determined. Thanks for the residual $Z_3$ symmetry, many lepton flavor violating decay modes are forbidden except for $τ\rightarrow μμ\bar{e}$ and $τ\rightarrow e e \barμ$. A mass limit of the flavon from these three-body decay modes is $60$~GeV taking into account the current experimental lower bounds at the Belle experiment. In our model, we predict a ratio of the branching ratios $τ\rightarrow μμ\bar{e}$ and $τ\rightarrow e e \barμ$ by using known charged lepton masses. We also find that the production cross section for the flavon can be $\mathcal{O}(1)$ fb. Thus the flavon would be found at the LHC run 2 by searching for 4-tau lepton signal.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑