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Andreas Crivellin. Overview of Flavor Physics with focus on the Minimal Supersymmetric Standard Model and two-Higgs-doublet models. Supported by a Marie Curie Intra-European Fellowship of the European Community's 7th Framework Programme under contract number (PIEF-GA-2012-326948). Outline:.
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Andreas Crivellin Overview of Flavor Physicswith focus on the Minimal Supersymmetric Standard Model and two-Higgs-doublet models Supported by a Marie Curie Intra-European Fellowship of the European Community's 7th Framework Programme under contract number (PIEF-GA-2012-326948).
Outline: • Introduction • Flavor observables • Meson mixing • Radiative B decays • Lepton flavor violation • Tauonic B decays • Flavor Phenomenology of 2HDMs • Conclusions
Flavor-Physics vs LHC • Direct searchesprobe the scale of NP ΛLimited by available energy • Flavor physicsprobes NP indirectly through loop effectsLimited by the size of flavor violation δ and the available statistics/precision
2HDM of type II(MSSM at tree-level) • One Higgs doublet couples only to down-quarks (and charged leptons), the other Higgs doubletcouples only to up-quarks. • 2 additional free parameters:tan(β)=vu/vd and the heavy Higgsmass (MSSM like Higgs potential) • All flavor-violations is due to the CKM matrix: neutral Higgs-quark couplings are flavor-conserving.
2HDM of type III • Both Higgs doublets couple simultaneously to up and down quarks. • The parameters describe flavor-changing neutral Higgs interactions • In the MSSM, are induced via loops
New SM predictions • Effect of includedDe Bruyn et al. 1204.1737 • New lattice result for HPQCD, FLAG • NLO electroweak correctionsBobeth et al. 1311.1348 • NNLO QCD correctionsHermann et al. 1311.1347 • Stringent constraints on scalar operators (e.g. Higgs induced flavor-violation) • Starting to probe vector operators
Constraints on NP models fromand Plot from David Straub’s talk
NNLO QCD corrections • Best constraints on the charged Higgs mass • Hadronic uncertainties largely drop out in the CP averaged BRBenzke et al. 1003.5012, Hurth et al. 1005.1224 Preliminary, M. Misiak, talk in Portoroz Hermann et al 1208.2788 AC, L. Mercolli 1106.5499
Meson mixing For an review see e.g. Lenz, Nierste et al. arXiv:1008.1593 • Kaon mixing • Very sensitive to NP with additional phases genericNP > 10000 TeVMost stringent constraints on extra dimensions • Bs, Bd mixing • Now in good agreement with the SM • D mixing • Poor SM prediction forthe mass difference due to non-perturbative effects • No sign for additional phases
Squark mass splitting in the MSSM:Constraints from Kaon and D mixing • Cancellations between different contributionsNon-degenerate squark masses are allowed • Interesting for LHC benchmark scenarios. Maximally allowed mass-splitting Alignment to Yd Constraints from D mixing Alignment to YuConstraints from Kaon mixing Minimally allowed mass-splitting AC, M. Davidkov 1002:2653
Lepton Flavour Violation • In the SM with massive neutrinos EXTREMELY small O(10-50)Observation of LFV would establish physics beyond the SM • best constraints on generic NP • conversionexcellent experimental prospectssensitive to Higgs mediated flavour-violation new predictions for the scalar-nucleon couplingsAC, M. Procura, M. Hoferichter 1312.4951 • Sensitive to flavour-changing Z effects Predicted ratio in the 2HDM
Tauonic B decays • Tree-level decays in the SM via W-boson • Sensitive to a charged Higgs due to the heavy tau lepton in the final state. All three observables are above the SM prediction
Type-II 2HDM • Allowed 2σ regions from:(superimposed) Tension from
B→τν in the 2HDM III • Constructive contribution to B→τν using is possible while satisfyingthe constraints from FCNCprocesses. Allowed regions from:
B→D(*)τν in the 2HDM III • B→D(*)τν and B→Dτν can be explained simultaneously using without violating bounds from FCNC processes. Allowed regions from: Check model via
Conclusions • Flavor-Physics puts stringent limits on NP • Nearly all measurements agree very well with the SM expectations • Tauonic B decays might be a hint for NP??? • A charged Higgs boson in a 2HDM with flavour-violation in the up sector might explain thisSearch for
Lepton flavour violating B decays Allowed regions respecting the constraints from and
Loop corrections to Higgs-quark couplings in the MSSM • Before electroweak symmetry breaking • After electroweak symmetry breaking One-to-one correspondence between Higgs-quark couplings and chirality changing self-energies. (In the decoupling limit)
NLO calculation of the quark self-energies Examplediagrams NLO calculation is important for: • Computation of effective Higgs-quark vertices. • Determination of the Yukawa couplings of the MSSM superpotential. Reduction of the matching scale dependence