Messages on Flavour Physics Beyond the Standard Model

Abstract

I present a brief summary of the main results on flavour physics beyond the Standard Model that have been obtained in 2008 by my collaborators and myself at the TUM. In particular I list main messages coming from our analyses of flavour and CP-violating processes in Supersymmetry, the Littlest Higgs model with T-Parity and a warped extra dimension model with custodial protection for flavour violating Z boson couplings. OvertureElementary particle physicists are eagerly awaiting the first messages from the LHC which, if we are lucky, will signal not only the discovery of the Higgs but also the existence of a definitive new physics beyond the Standard Model (SM) of elementary interactions of quarks and leptons.We need more than the SM in order to understand several observed facts, in particular the huge hierarchy between the Planck scale and the electroweak scale and the hierarchies in quark and lepton mass spectra and in their flavour violating interactions summarized by the CKM and PMNS mixing matrices, respectively. There are of course many other known reasons for going beyond the SM and expecting new physics at scales probed by the LHC but I will not repeat them here. While a large fraction of particle physicists bets that this new physics will be supersymmetry, the turbulences on stock markets in this decade teach us that it is wise to have many different shares.In this note I would like to report on the results of various analyses of physics beyond the SM performed by my young and strong collaborators and myself at the Technical University Munich in 2008 [1,2,3,4,5,6,7,8,9].In view of space limitations this presentation will consist basically of a list of messages that summarizes the main results of our papers on new physics, in particular supersymmetry, the Littlest Higgs model with T-parity (LHT) and the Randall-Sundrum (RS) scenario with all particles except the Higgs propagating in the bulk.All our papers deal with flavour violating processes, in particular CP-violating ones. While in these papers we have hopefully cited properly all relevant papers, the list of references presented here is incomplete and I apologize for it. ε K -An Old Star Strikes BackOne of the many successes of the SM is particularly striking. The SM is consistent within theoretical and parametric uncertainties simultaneously with |ε K | ≈ 2.2 · 10 −3 that measures tiny This situation may change soon due to the following recent developments:• Improved lattice calculations ofB K . In particular a recent simulation with dynamical fermions results inB K = 0.72 ± 0.04[10] that should be improved in the coming months,• Inclusion of additional corrections to ε K [1] that were usually neglected in the literature in view of the 20% error onB K . As this parameter is now much better known it is mandatory to include them. Effectively 1

Unanswered Questions in the Electroweak Theory

“…The unitarity triangle analysis is mainly sensitive to processes that change flavor by two units. Even in the wellstudied rare K and B decays (flavor change by one unit), many examples of new physics that could have passed the unitarity-triangle screen-supersymmetry, little Higgs models with T -parity, and warped extra dimensionscould give large departures [100]. New sources of CP violation and FCNC occur in models that do not enforce minimal flavor violation.…”

Electroweak and flavour structure of a warped extra dimension with custodial protection

“…The most important result of the present paper are the Feynman rules collected in Appendix D. These rules allowed already to perform two detailed phenomenological analyses of ∆F = 2 FCNC processes in the quark sector [27] and those ∆F = 1 rare K and B decays in which new physics contributions enter already at the tree level [44]. Short reviews of these results can be found in [78][79][80]. The analyses of processes with dipole operators like B → X s γ, µ → eγ, and electric dipole moments, where new physics enters first at the one-loop level will be presented elsewhere.…”