Tree level gauge mediation (TGM) may be considered as the simplest way to communicate supersymmetry breaking: through the tree level renormalizable exchange of heavy gauge messengers. We study its general structure, in particular the general form of tree level sfermion masses and of one loop, but enhanced, gaugino masses. This allows us to set up general guidelines for model building and to identify the hypotheses underlying the phenomenological predictions. In the context of models based on the "minimal" gauge group SO(10), we show that only two "pure" embeddings of the MSSM fields are possible using $d< 120$ representations, each of them leading to specific predictions for the ratios of family universal sfermion masses at the GUT scale, $m^2_{\bar{5}} = 2 m^2_{10}$ or $m^2_{\bar{5}} = (3/4) m^2_{10}$ (in SU(5) notation). These ratios are determined by group factors and are peculiar enough to make this scheme testable at the LHC. We also discuss three possible approaches to the $μ$-problem, one of them distinctive of TGM.
We show that in gauge mediation models with tree-level R-symmetry breaking where supersymmetry and R-symmetries are broken by different fields, the gaugino mass either vanishes at one loop or finds a contribution from loop-level R-symmetry breaking. Thus tree-level R-symmetry breaking for phenomenology is either no-go or redundant in the simplest type of models. Including explicit messenger mass terms in the superpotential with a particular R-charge arrangement is helpful to bypass the no-go theorem, and the resulting gaugino mass is suppressed by the messenger mass scale.
A simple model for the explanation of the muon anomalous magnetic moment was proposed by the present authors within the context of the minimal supersymmetric standard model [1607.05705, 1608.06618]: "Higgs-anomaly mediation". In the setup, squarks, sleptons, and gauginos are massless at tree-level, but the Higgs doublets get large negative soft supersymmetry (SUSY) breaking masses squared $m_{H_u}^2 \simeq m_{H_d}^2 < 0$ at a certain energy scale, $M_{\rm inp}$. The sfermion masses are radiatively generated by anomaly mediation and Higgs-loop effects, and gaugino masses are solely determined b…
Phenomenology of the triplet seesaw mechanism with Gauge and Yukawa mediation of SUSY breaking
我们深入讨论了一种新的超对称大统一情形，即重SU（2）W三重态交换产生中微子质量和软超对称破缺项的三重态跷跷板机制.这个框架，最近提出的我们在以前的工作，是高度预测，因为它只包含三个自由参数连接低能量中微子参数，轻子和夸克味破坏，sparticle和希格斯玻色子光谱和电弱对称性击穿。这三个参数是三重态质量M_T、有效超对称性破缺尺度B_T和耦合常数λ。我们进行了一个完整的分析的参数空间，考虑到目前的实验限制，并考虑不同类型的中微子光谱。一个特别强调的sparticle和希格斯光谱的特定功能和模型独立的预测得到的过程μ-> e X，μ-> e转换的核，tau-> e Y和tau-> mu Y（X =伽马，e e，Y=伽马，e e，mu）。在附录中，我们提出了一些与我们的分析相关的技术方面。
We investigate several phenomena related to FCNCs in the $\text{3-3-1-1}$ model. The sources of FCNCs at the tree-level from both the gauge and Higgs sectors are clarified. Experiments on the oscillation of mesons most stringently constrain the tree-level FCNCs. The lower bound on the new physics scale is imposed more tightly than in the previous, $\text{M}_{\text{new}}>12 $ \text{TeV}. Under this bound, the tree-level FCNCs make a negligible contribution to the $\text{Br}(B_s \rightarrow μ^+ μ^-)$, $\text{Br}(B \rightarrow K^{*} μ^+ μ^-)$ and $\text{Br}(B^{+}\rightarrow K^{+}μ^{+}μ^{-})$. The…
In this paper we discuss the Bhabha and Compton scattering for the quantum electrodynamics defined in the framework of very special relativity (VSR). The main aspect of the VSR setting is that it admits different types of interactions appearing in a nonlocal form due to the modified gauge invariance. We explore the richness of these new couplings in the evaluation of the differential cross-section for these tree-level processes. We assess the behavior of the leading VSR Lorentz violation modifications by considering some special limits for the Bhabha and Compton cross-section expressions.
We consider aspects of tree and one-loop behavior in a generic 4d EFT of massless scalars, fermions, and vectors, with a particular eye to the high-energy limit of the Standard Model EFT at operator dimensions 6 and 8. First, we classify the possible Lorentz structures of operators and the subset of these that can arise at tree-level in a weakly coupled UV completion, extending the tree/loop classification through dimension 8 using functional methods. Second, we investigate how operators contribute to tree and one-loop helicity amplitudes, exploring the impact of non-renormalization theorems t…
