Flavor Changing Heavy Higgs Interactions at the LHC

Abstract

A general two Higgs doublet model (2HDM) is adopted to study the signature of flavor changing neutral Higgs (FCNH) decay ${\varphi }^0\to t\bar{c}+\bar{t}c$, where ${\varphi }^0$ could be a CP-even scalar ($H^0$) or a CP-odd pseudoscalar ($A^0$). Measurement of the light 125 GeV neutral Higgs boson ($h^0$) couplings at the Large Hadron Collider (LHC) favor the decoupling limit or the alignment limit of a 2HDM, in which gauge boson and diagonal fermion couplings of $h^0$ approach Standard Model values. In such limit, FCNH couplings of $h^0$ are naturally suppressed by a small mixing parameter $\cos (\beta -\alpha )$, while the off-diagonal couplings of heavier neutral scalars ${\varphi }^0$ are sustained by $\sin (\beta -\alpha )\sim 1$. We study physics background from dominant processes with realistic acceptance cuts and tagging efficiencies. Promising results are found for the LHC running at 13 or 14 TeV collision energies.

Comments: 14 pages, 5 figures, to be published in Phys. Lett. B