Extraordinary phenomenology from warped flavor triviality

Self Cite

The CDF collaboration has recently reported a large deviation from the standard model of the tt forward-backward asymmetry in the high invariant mass region. We interpret this measurement as coming from new physics at a heavy scale Λ , and perform a model-independent analysis up to O(1/Λ 4 ) . A simple formalism to test and constrain models of new physics is provided. We find that a large asymmetry cannot be accommodated by heavy new physics that does not interfere with the standard model. We show that a smoking gun test for the heavy new physics hypothesis is a significant deviation from the standard model prediction for the tt differential cross section at large invariant mass. At M tt > 1 TeV the cross section is predicted to be at least twice that of the SM at the Tevatron, and for M tt > 1.5 TeV at least three times larger than the SM at the LHC.

Section: Introductionmentioning

confidence: 99%

Implications of the CDF $ t\bar{t} $ forward-backward asymmetry for hard top physics

Delaunay

Gedalia

Hochberg

et al. 2011

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“…Generically in CH models, M KK < 1 TeV is required for a fully natural Higgs mass, while the flavor bounds require M KK > 10-20 TeV. To this end, flavor symmetries have been introduced to reconcile flavor bounds with naturalness [40][41][42][43][44][45][46][47][48].…”

Section: Jhep09(2016)146mentioning

confidence: 99%

The flavor of the Composite Twin Higgs

Csáki

Geller

Telem

et al. 2016

The assumption of anarchic quark flavor puts serious stress on composite Higgs models: flavor bounds imply a tuning of a few per-mille (at best) in the Higgs potential. Composite twin Higgs (CTH) models significantly reduce this tension by opening up a new region of parameter space, obtained by raising the coupling among the composites close to the strong coupling limit g * ∼ 4π, thereby raising the scale of composites to around 10 TeV. This does not lead to large tuning in the Higgs potential since the leading quantum corrections are canceled by the twin partners (rather than the composites). We survey the leading flavor bounds on the CTH, which correspond to tree-level ∆F = 2 four-Fermi operators from Kaluza-Klein (KK) Z exchange in the kaon system and 1-loop corrections from KK fermions to the electric dipole moment of the neutron. We provide a parametric estimate for these bounds and also perform a numeric scan of the parameter space using the complete calculation for both quantities. The results confirm our expectation that CTH models accommodate anarchic flavor significantly better than regular composite Higgs (CH) models. Our conclusions apply both to the identical and fraternal twin cases.

“…This possibility leads to a series of interesting experimental consequences which have been partially discussed in ref. [31,32,[34][35][36][37]. We focus here on analysing signals which could be already probed by direct searches at the LHC.…”

Section: Jhep02(2014)055mentioning

confidence: 99%

Light non-degenerate composite partners at the LHC

Delaunay

Flacke

González-Fraile

et al. 2014

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Abstract:We study the phenomenological implications of a large degree of compositeness for the light generation quarks in composite pseudo-Nambu-Goldstone-boson Higgs models. We focus in particular on phenomenologically viable scenarios where the right-handed uptype quarks have a sizable mixing with the strong dynamics. For concreteness we assume the latter to be characterized by an SO(5)/SO(4) symmetry with fermionic resonances in the SO(4) singlet and fourplet representations. Singlet partners dominantly decay to a Higgs boson and jets. Since no dedicated searches are currently looking for these final states, singlet partners can still be rather light. Conversely, some fourplet partner components dominantly decay to an electroweak gauge boson and a jet, a type of signature which has been analysed at the LHC. We have reinterpreted various ATLAS and CMS analyses in order to constrain the parameter space of this class of models. In the limit of first two generation degeneracy, as in minimal flavor violation or U(2)-symmetric flavor models, fourplet partners need to be relatively heavy, with masses above 1.8 TeV, or the level of compositeness needs to be rather small. The situation is significantly different in models which deviate from the first two generation degeneracy paradigm, as charm quark parton distribution functions are suppressed relative to the up quark ones. We find that JHEP02 (2014)055 the right-handed charm quark component can be mostly composite together with their partners being as light as 600 GeV, while the right-handed up quark needs either to be mostly elementary or to have partners as heavy as 2 TeV. Models where right-handed uptype quarks are fully composite fermions are also analysed and yield qualitatively similar conclusions. Finally, we consider the case where both the fourplet and the singlet states are present. We demonstrate that in this case the fourplet bounds could be significantly weaken due to a combination of smaller production rates and the opening of new channels including cascade processes.