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Minimal Flavour Violation: an effective field theory approach

G. D'Ambrosio·G. F. Giudice·G. Isidori·A. Strumia
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Abstract

We present a general analysis of extensions of the Standard Model which satisfy the criterion of Minimal Flavour Violation (MFV). We define this general framework by constructing a low-energy effective theory containing the Standard Model fields, with one or two Higgs doublets and, as the only source of SU(3)^5 flavour symmetry breaking, the background values of fields transforming under the flavour group as the ordinary Yukawa couplings. We analyse present bounds on the effective scale of dimension-six operators, which range between 1 and 10 TeV, with the most stringent constraints imposed by B -> X_s gamma. In this class of theories, it is possible to relate predictions for FCNC processes in B physics to those in K physics. We compare the sensitivity of various experimental searches in probing the hypothesis of MFV. Within the two-Higgs-doublet scenario, we develop a general procedure to obtain all tan(beta)-enhanced Higgs-mediated FCNC amplitudes, discussing in particular their impact in B -> l^+l^-, Delta M_B and B -> X_s gamma. As a byproduct, we derive some two-loop tan(beta)-enhanced supersymmetric contributions to B -> X_s gamma previously unknown.

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G. D'Ambrosio, G. F. Giudice, G. Isidori, A. Strumia. 2002-08-08. Minimal Flavour Violation: an effective field theory approach. https://doi.org/10.1016/s0550-3213(02)00836-2

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