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Up Asymmetries From Exhilarated Composite Flavor Structures
We present a class of warped extra dimension (composite Higgs) models which
conjointly accommodates the t\bar t forward-backward asymmetry observed at the
Tevatron and the direct CP asymmetry in singly Cabibbo suppressed D decays
first reported by the LHCb collaboration. We argue that both asymmetries, if
arising dominantly from new physics beyond the Standard Model, hint for a
flavor paradigm within partial compositeness models in which the right-handed
quarks of the first two generations are not elementary fields but rather
composite objects. We show that this class of models is consistent with current
data on flavor and CP violating physics, electroweak precision observables,
dijet and top pair resonance searches at hadron colliders. These models have
several predictions which will be tested in forthcoming experiments. The CP
asymmetry in D decays is induced through an effective operator of the form
(\bar u c)_{V+A}(\bar s s)_{V+A} at the charm scale, which implies a larger CP
asymmetry in the D^0\to K^+K^- rate relative the D^0\to \pi^+\pi^- channel.
This prediction is distinctive from other Standard Model or dipole-based new
physics interpretation of the LHCb result. CP violation in D-\bar D mixing as
well as an an excess of dijet production of the LHC are also predicted to be
observed in a near future. A large top asymmetry originates from the exchange
of an axial resonance which dominantly produces left-handed top pairs. As a
result a negative contribution to the lepton-based forward-backward asymmetry
in t\bar t production, as well as O(10%) forward-backward asymmetry in b\bar b
production above m_{b\bar b}\simeq 600GeV at the Tevatron is expected.Comment: 35 pages, 7 fig
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