标题： 低能探测无尺度SU(5)超大统一理论 显示英文标题

标题： Low-Energy Probes of No-Scale SU(5) Super-GUTs

摘要： 我们探讨在无尺度SU(5)超大统一理论模型中，$\mu \to e \gamma$分支比、$\text{BR}(\mu\rightarrow e\gamma)$和电子电偶极矩(eEDM)$d_e$的可能值，这些模型在高于大统一尺度$M_{\rm GUT}$的某个高输入尺度$M_{\rm in}$处，软超对称破缺物质标量质量消失的边界条件。 我们考虑了宇宙学冷暗物质密度$\Omega_{CDM} h^2$、希格斯粒子质量$M_h$以及实验上对$p \to K^+ \bar \nu$寿命的下限约束，这是这些超大统一理论模型中主要的质子衰变模式。 将这一限制与$\Omega_{CDM} h^2$和$M_h$相协调需要负责电荷为 2/3 的夸克质量的希格斯场被扭曲，并且可能还需要负责电荷为 1/3 和带电轻子质量的希格斯场，这取决于模型的软超对称性破缺质量。 我们考虑了六种可能的超大统一理论初始条件模型，以及两种可能的夸克味混合选择，将它们对质子衰变的预测与忽略混合效应的模型版本进行对比。 我们发现，当考虑到暗物质密度、希格斯质量以及当前质子衰变的约束时，$\tau\left(p\rightarrow K^+ \bar{\nu}\right)$可能会被即将进行的Hyper-Kamiokande实验所探测到，而所有模型都预测$\text{BR}(\mu\rightarrow e\gamma)$和$d_e$低于当前和未来实验的灵敏度，或者两种味道选择都如此。然而，在两个模型中，有一种味道选择的有限区域内，$\mu \to e$在重核上的转换在未来可能被观测到。我们的结果表明，在我们考虑的无尺度模型类中不存在超对称味问题。 显示英文摘要

摘要： We explore the possible values of the $\mu \to e \gamma$ branching ratio, $\text{BR}(\mu\rightarrow e\gamma)$, and the electron dipole moment (eEDM), $d_e$, in no-scale SU(5) super-GUT models with the boundary conditions that soft supersymmetry-breaking matter scalar masses vanish at some high input scale, $M_{\rm in}$, above the GUT scale, $M_{\rm GUT}$. We take into account the constraints from the cosmological cold dark matter density, $\Omega_{CDM} h^2$, the Higgs mass, $M_h$, and the experimental lower limit on the lifetime for $p \to K^+ \bar \nu$, the dominant proton decay mode in these super-GUT models. Reconciling this limit with $\Omega_{CDM} h^2$ and $M_h$ requires the Higgs field responsible for the charge-2/3 quark masses to be twisted, and possibly also that responsible for the charge-1/3 and charged-lepton masses, with model-dependent soft supersymmetry-breaking masses. We consider six possible models for the super-GUT initial conditions, and two possible choices for quark flavor mixing, contrasting their predictions for proton decay with versions of the models in which mixing effects are neglected. We find that $\tau\left(p\rightarrow K^+ \bar{\nu}\right)$ may be accessible to the upcoming Hyper-Kamiokande experiment, whereas all the models predict $\text{BR}(\mu\rightarrow e\gamma)$ and $d_e$ below the current and prospective future experimental sensitivities or both flavor choices, when the dark matter density, Higgs mass and current proton decay constraints are taken into account. However, there are limited regions with one of the flavor choices in two of the models where $\mu \to e$ conversion on a heavy nucleus may be observable in the future. Our results indicate that there is no supersymmetric flavor problem in the class of no-scale models we consider.