Scotogenic Models Predict New Asymmetries in Lepton Decays

Researchers have re-evaluated a specific class of scotogenic models, known as "T1-2-A", which aim to simultaneously explain neutrino oscillation data and propose a viable dark matter candidate. The study focused on charged lepton flavor violating (cLFV) decays, particularly in rare muon transitions. The results suggest that these models can predict significant rates for cLFV observables, opening new avenues for experimental detection. The work explores in detail the model's parameter space, identifying regions where cLFV rates are appreciable. Furthermore, the scientists have considered the role of parity and time-reversal asymmetries in three-body lepton decays, specifically in processes like $\ell_\alpha^+ \to \ell_\beta^+ \ell_\gamma^+ \ell_\delta^-$. These asymmetries could be experimentally investigated in association with polarized muon and tau decays. The inclusion of these new observables offers complementary information on the "T1-2-A" scotogenic model, providing additional means to test its validity. If these asymmetries or the predicted cLFV rates were detected, it would strengthen the hypothesis that these models can describe phenomena beyond the Standard Model, such as the nature of dark matter and the origin of neutrino masses.

Re-evaluating Supersymmetry Limits with LHC Data

A new study has re-examined the constraints imposed by the Large Hadron Collider (LHC) on supersymmetry (SUSY), focusing on the electroweak-ino sector. Using public data from ATLAS Run 2 searches, researchers employed the SModelS v3.0 tool to reproduce and extend the original analysis, also incorporating results from the CMS experiment. This work is crucial for understanding which regions of the vast SUSY parameter space remain unexplored or are compatible with current observations. The ATLAS collaboration recently published an extensive scan of the phenomenological Minimal Supersymmetric Standard Model (pMSSM), with a particular focus on electroweak-inos, which are the supersymmetric partners of gauge and Higgs bosons. This scan aimed to determine how searches for electroweak production of SUSY particles in LHC Run 2 constrained this model. The simulation data (SLHA files) and the constraints from eight individual searches were made publicly available, allowing other research groups to validate and expand upon the results. The research team used this data to evaluate the capability of SModelS v3.0 to replicate the ATLAS constraints. Furthermore, they explored how the inclusion of CMS results alters the picture and what benefits are gained from the statistical combination of analyses from both experiments. The results underscore the need for a broad, multifaceted approach to maximize sensitivity and close loopholes in the extensive SUSY parameter space. The study also discusses the part of the parameter space with light electroweak-inos that remains valid despite the stringent LHC limits, indicating that supersymmetry is not ruled out, but its manifestations might be more subtle than anticipated.