Searching for New Physics with Flavor Violating Observables

In this talk, I review the status and prospects of several low energy flavor observables that are highly sensitive to New Physics effects. In particular I discuss the implications for possible New Physics in b --> s transitions coming from the recent experimental results on the B_s mixing phase, the branching ratio of the rare decay B_s --> mu+mu-, and angular observables in the B --> K* mu+mu- decay. Also the recent evidence for direct CP violation in singly Cabibbo suppressed charm decays and its interpretation in the context of New Physics models is briefly discussed.Comment: 8 pages, 2 figures, contribution to the proceedings of "Les Rencontres de Physique de la Vallee d'Aoste", La Thuile, Italy, February 26 - March 3, 201

Phenomenology of CP Violation in a Flavor Blind MSSM and Beyond

We present an analysis of low energy CP violating observables in the Minimal Supersymmetric Standard Model (MSSM). We focus on the predictions of CP violation in b -> s transitions in the framework of a flavor blind MSSM, where the CKM matrix remains the only source of flavor violation, but additional CP violating phases are introduced in the soft SUSY breaking sector. We find large and strongly correlated effects in Delta F = 0 observables like the electric dipole moments (EDMs) of the electron and the neutron, as well as in Delta F = 1 observables like the time dependent CP asymmetries in B -> phi K_s and B -> eta' K_s, the direct CP asymmetry in b -> s gamma and in several CP asymmetries in B -> K* mu+ mu-. On the other hand, observables that are only sensitive to CP violation in Delta F = 2 transitions, in particular the B_s mixing phase, are found to be SM like in this framework. We stress that only in presence of additional sources of flavor violation, sizeable New Physics effects to CP violation in meson mixing can occur.Comment: 4 pages, 1 figure, submitted to the proceedings of the 17th International Conference on Supersymmetry and the Unification of Fundamental Interactions (SUSY 09), Boston, MA, June 5-10, 200

New physics in b→sb\to s transitions after LHC run 1

We present results of global fits of all relevant experimental data on rare $b \to s$ decays. We observe significant tensions between the Standard Model predictions and the data. After critically reviewing the possible sources of theoretical uncertainties, we find that within the Standard Model, the tensions could be explained if there are unaccounted hadronic effects much larger than our estimates. Assuming hadronic uncertainties are estimated in a sufficiently conservative way, we discuss the implications of the experimental results on new physics, both model independently as well as in the context of the minimal supersymmetric standard model and models with flavour-changing $Z'$ bosons. We discuss in detail the violation of lepton flavour universality as hinted by the current data and make predictions for additional lepton flavour universality tests that can be performed in the future. We find that the ratio of the forward-backward asymmetries in $B \to K^* \mu^+\mu^-$ and $B \to K^* e^+e^-$ at low dilepton invariant mass is a particularly sensitive probe of lepton flavour universality and allows to distinguish between different new physics scenarios that give the best description of the current data.Comment: 49 pages, 12 figures. v4: matches version published in EPJ

Indirect Probes of the MSSM after the Higgs Discovery

We study the minimal supersymmetric standard model (MSSM) with minimal flavor violation (MFV), imposing constraints from flavor physics observables and MSSM Higgs searches, in light of the recent discovery of a 125 GeV Higgs boson by ATLAS and CMS. We analyze the electroweak vacuum stability conditions to further restrict the MSSM parameter space. In addition, a connection to ultraviolet physics is shown via an implementation of renormalization group running, which determines the TeV-scale spectrum from a small set of minimal supergravity parameters. Finally, we investigate the impact from dark matter direct detection searches. Our work highlights the complementarity of collider, flavor and dark matter probes in exploring the MSSM, and shows that even in a MFV framework, flavor observables constrain the MSSM parameter space well beyond the current reach of direct SUSY particle searches.Comment: 28 pages, 15 figures; v2, updated with new LHCb and direct A->tau tau results from HCP 2012, references adde

Status of the B→K∗μ+μ−B\to K^*\mu^+\mu^- anomaly after Moriond 2017

Motivated by recent results by the ATLAS and CMS collaborations on the angular distribution of the $B \to K^* \mu^+\mu^-$ decay, we perform a state-of-the-art analysis of rare $B$ meson decays based on the $b \to s \mu \mu$ transition. Using standard estimates of hadronic uncertainties, we confirm the presence of a sizable discrepancy between data and SM predictions. We do not find evidence for a $q^2$ or helicity dependence of the discrepancy. The data can be consistently described by new physics in the form of a four-fermion contact interaction $(\bar s \gamma_\alpha P_L b)(\bar \mu \gamma^\alpha \mu)$. Assuming that the new physics affects decays with muons but not with electrons, we make predictions for a variety of theoretically clean observables sensitive to violation of lepton flavour universality.Comment: 20 pages, 8 figures, 3 tables. v3: numerics updated using v2 of arXiv:1606.04731. Conclusions unchanged. Matches published version. Example script available at https://github.com/DavidMStraub/paper-bkstarmumu-ans