As a joint explanation for the dark matter (DM) problem and the muon $(g-2)$ anomaly, we propose a simplified model of lepton-flavoured complex scalar DM with couplings to both the left- and right-handed leptons of the Standard Model (SM). Both interactions are governed by the same new flavour-violating coupling matrix $λ$, however we allow for a relative scaling of the coupling strength. The SM is further extended by two fermion representations, transforming as an $SU(2)_L$ doublet and singlet, respectively, and mediating these interactions. The fermions additionally couple to the SM Higgs doublet via a new Yukawa coupling. To study the model's phenomenology we first investigate constraints from collider searches, flavour experiments, precision tests of the SM, the DM relic density, and direct as well as indirect detection experiments individually. We then perform a combined analysis by demanding that all mentioned constraints are satisfied simultaneously. We use the results of this combined analysis and examine if the model is capable of accommodating the $(g-2)_μ$ anomaly within its viable parameter space without introducing fine-tuned lepton masses. For all benchmark scenarios we consider, we find that the central value of $Δa_μ^\text{exp}$ can be reached without generating too large corrections to the lepton masses. We hence conclude that this model qualifies as a viable and attractive lepton-flavoured DM model that at the same time solves the $(g-2)_μ$ anomaly.
B-physics anomalies: The bridge between R-parity violating Supersymmetry and flavoured Dark Matter
近年来,已经积累了大量的实验迹象,表明在B衰变中,涉及$b \to c τν$和$b \to s \ell^+ \ell^-$的轻子味普适性破坏效应。一个可能的新物理学解释可以在R-宇称破坏超对称性的框架内寻求,它包含了通过轻子夸克,树级交换和涉及纯轻子相互作用的单圈图来解释异常的必要成分。此外,一个近似的$U(2)^2$味对称,尊重规范耦合统一,成功地控制这些相互作用的强度。然而,来自轻子过程和$Z$玻色子衰变的强约束排除了$2 σ$水平上的大部分相关参数空间。此外,R宇称破坏剥夺了超对称性的暗物质候选者。出于这些不足之处,我们引入了一个新的规范单线态超场,根据味对称性收费,并表明其第三代,标量分量可能会参与回路图,缓解上述紧张局势,而在同一时间重现所观察到的遗迹丰度。我们得到了一个解决方案,这两个异常,也是完全符合丰富的味道和暗物质现象。最后,我们评估了在未来实验中探索该模型的前景。
Electric dipole moments from flavoured CP violation in SUSY
所谓的超对称味和CP问题与味的起源有很深的关系,因此也与SM汤川耦合本身的起源有很深的关系。我们表明,现实的SU(3)味对称性与自发CP破坏正确再现SM汤川矩阵可以同时解决这两个问题,而无需特别修改的超对称模型。我们分析了这些模型中的轻子电偶极矩和轻子味破坏过程。我们表明,电子EDM和衰变μ-> e γ自然是在拟议的实验范围内,如果sfermion质量是可测量的大型强子对撞机。
FCNC and CP Violation Observables in a SU(3)-flavoured MSSM
最小超对称标准模型的非阿贝尔味对称性可以解释汤川耦合的味结构,同时解决超对称味问题。类似地,如果CP在风味区段中自发地被破坏,则超对称CP问题可以被解决。在这项工作中,我们提出了一个明确的例子,这些声明与SU(3)味对称性和自发的CP破坏。此外,我们表明,它仍然是可能的,找到一些重大偏离SM的期望,就FCNC和CP破坏而言。我们发现轻子味破坏衰变如$μ\to e γ$和$τ\to μγ$、电偶极矩$d_e$和$d_n$以及K介子CP破坏过程如$ε_K$都有很大的贡献。因此,这些风味MSSM的实现是现象敏感的风味和CP vioation物理领域的实验研究。
Learning about flavour structure from tau to ell gamma and mu to e gamma?
目前和即将进行的实验应该可以将辐射轻子衰变的灵敏度提高一个数量级。本文假设τ->(e,μ)γ衰变之一被观察到,并探讨了所需的新的风味耦合的结构和后果。在简单的模型(一个低尺度的跷跷板,leptoquarks),它示出的偶极顶点函数是成比例的产品的风味矩阵从拉格朗日(一个“Jarlskog样”不变),只要环粒子弱耦合到希格斯玻色子。其次,如果偶极顶点函数具有分层结构,则这可能意味着由于mu --> e gamma上的界限所暗示的“近似零”,因此只能观察到一些tau -->(e,mu)gamma模式。这种潜在的测试的层次结构的假设进行了讨论。