8 research outputs found
Universal Constraints on Low-Energy Flavour Models
It is pointed out that in a general class of flavour models one can identify
certain universally present FCNC operators, induced by the exchange of heavy
flavour messengers. Their coefficients depend on the rotation angles that
connect flavour and fermion mass basis. The lower bounds on the messenger scale
are derived using updated experimental constraints on the FCNC operators. The
obtained bounds are different for different operators and in addition they
depend on the chosen set of rotations. Given the sensitivity expected in the
forthcoming experiments, the present analysis suggests interesting room for
discovering new physics. As the highlights emerge the leptonic processes,
, and
conversion in nuclei.Comment: 18 pages, 3 figures; v2 matches published versio
The Messenger Sector of SUSY Flavour Models and Radiative Breaking of Flavour Universality
The flavour messenger sectors and their impact on the soft SUSY breaking
terms are investigated in SUSY flavour models. In the case when the flavour
scale M is below the SUSY breaking mediation scale M_S, the universality of
soft terms, even if assumed at M_S, is radiatively broken. We estimate this
effect in a broad class of models. In the CKM basis that effect gives flavour
off-diagonal soft masses comparable to the tree-level estimate based on the
flavour symmetry.Comment: 24 pages, 3 figures. v3: minor changes in the text, typos corrected,
version accepted for publication in JHE