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The experimental value for the isospin amplitude ReA 2 in K → ππ decays has been successfully explained within the Standard Model (SM), both within large N approach to QCD and by QCD lattice calculations. On the other hand within large N approach the value of ReA 0 is by at least 30% below the data. While this deficit could be the result of theoretical uncertainties in this approach and could be removed by future precise QCD lattice calculations, it cannot be excluded that the missing piece in ReA 0 comes from New Physics (NP). We demonstrate that this deficit can be significantly softened by tree-level FCNC transitions mediated by a heavy colourless Z gauge boson with flavour violating left-handed coupling ∆ sd L (Z ) and approximately universal flavour diagonal right-handed coupling ∆ qq R (Z ) to quarks. The approximate flavour universality of the latter coupling assures negligible NP contributions to ReA 2 . This property together with the breakdown of GIM mechanisms at tree-level allows to enhance significantly the contribution of the leading QCD penguin operator Q 6 to ReA 0 . A large fraction of the missing piece in the ∆I = 1/2 rule can be explained in this manner for M Z in the reach of the LHC, while satisfying constraints from ε K , ε /ε, ∆M K , LEP-II and the LHC. The presence of a small right-handed flavour violating coupling ∆ sd R (Z ) ∆ sd L (Z ) and of enhanced matrix elements of ∆S = 2 left-right operators allows to satisfy simultaneously the constraints from ReA 0 and ∆M K , although this requires some fine-tuning. We identify quartic correlation between Z contributions to ReA 0 , ε /ε, ε K and ∆M K . The tests of this proposal will require much improved evaluations of ReA 0 and ∆M K within the SM, of Q 6 0 as well as precise tree level determinations of |V ub | and |V cb |. We present correlations between ε /ε, K + → π + ν ν and K L → π 0 ν ν with and without the ∆I = 1/2 rule constraint and generalize the whole analysis to Z with colour (G ) and Z with FCNC couplings. In the latter case no improvement on ReA 0 can be achieved without destroying the agreement of the SM with the data on ReA 2 . Moreover, this scenario is very tightly constrained by ε /ε. On the other hand in the context of the ∆I = 1/2 rule G is even more effective than Z : it provides the missing piece in ReA 0 for M G = (3.5 − 4.0) TeV.

We use QCD sum rules to calculate the hadronic matrix elements governing the rare decays B → Kℓ + ℓ − and B → K * ℓ + ℓ − induced by the flavour changing neutral current b → s transition. We also study relations among semileptonic and rare B → K ( * ) decay form factors. The analysis of the invariant mass distribution of the lepton pair in B → K ( * ) ℓ + ℓ − and of the angular asymmetry in B → K * ℓ + ℓ − provides us with interesting tests of the Standard Model and its extensions.

SuperB is a high luminosity e + e − collider that will be able to indirectly probe new physics at energy scales far beyond the reach of any man made accelerator planned or in existence. Just as detailed understanding of the Standard Model of particle physics was developed from stringent constraints imposed by flavour changing processes between quarks, the detailed structure of any new physics is severely constrained by flavour processes. In order to elucidate this structure it is necessary to perform a number of complementary studies of a set of golden channels. With these measurements in hand, the pattern of deviations from the Standard Model behavior can be used as a test of the structure of new physics. If new physics is found at the LHC, then the many golden measurements from SuperB will help decode the subtle nature of the new physics. However if no new particles are found at the LHC, SuperB will be able to search for new physics at energy scales up to 10 − 100 TeV. In either scenario, flavour physics measurements that can be made at SuperB play a pivotal role in understanding the nature of physics beyond the Standard Model. Examples for using the interplay between measurements to discriminate New Physics models are discussed in this document.SuperB is a Super Flavour Factory, in addition to studying large samples of B u,d,s , D and τ decays, SuperB has a broad physics programme that includes spectroscopy both in terms of the Standard Model and exotica, and precision measurements of sin 2 θ W . In addition to performing CP violation measurements at the Υ (4S) and φ(3770), SuperB will test CP T in these systems, and lepton universality in a number of different processes. The multitude of rare decay measurements possible at SuperB can be used to constrain scenarios of physics beyond the Standard Model. In terms of other precision tests of the Standard Model, this experiment will be able to perform precision over-constraints of the unitarity triangle through multiple measurements of all angles and sides.