Enhancing the Higgs associated production with a top quark pair

Marcin Badziak
UC Berkeley
Wednesday, March 8, 2017
3:00 pm
FRH 4135

Precision measurements of the 125 GeV Higgs resonance recently discovered at the LHC have determined that its properties are similar to the ones of the Standard Model (SM) Higgs boson. However, the current uncertainties in the determination of the Higgs boson couplings leave room for significant deviations from the SM expectations. In fact, if one assumes no correlation between the top-quark and gluon couplings to the Higgs, the global fit to the Higgs data leads to central values of the Higgs couplings to the top (bottom) quark  that are about 2\sigma above (below) the SM predictions. This deviation originates mainly from observed by ATLAS and CMS, in both 8 and 13 TeV runs of the LHC, enhanced Higgs associated production with a top quark pair. We show that this can be explained in the framework of type-II Two-Higgs-Doublet Model (2HDM) supplemented by new light colored particles. As an interesting example, we demonstrate that the observed deviations from the SM expectations can be accommodated in the Next-to-Minimal-Supersymmetric extension of the SM (NMSSM) with light stops. This scenario leads to rich phenomenology of light non-SM-like Higgses with many signatures that are not looked for in existing LHC searches. 

Sheldon Campbell
Iftah Galon
Felix Kling
Sebastian Trojanowski