Top decays with flavor changing neutral Higgs interactions at the LHC

We investigate the prospects for discovering a top quark decaying into one light Higgs boson along with a charm quark in top quark pair production at the CERN Large Hadron Collider (LHC). A general two Higgs doublet model is adopted to study the signature of flavor changing neutral Higgs decay t → c ϕ 0 , where ϕ 0 could be CP-even ( H 0 ) or CP-odd ( A 0 ). The dominant physics background is evaluated with realistic acceptance cuts as well as tagging and mistagging efficiencies. For a reasonably large top–charm–Higgs coupling ( λ tc / λ t ≳ 0.09 ), the abundance of signal events and the reduction in physics background allow us to establish a 5 σ signal for M ϕ ∼ 125 GeV at the LHC with a center of mass energy ( s ) of 8 TeV and an integrated luminosity of 20 fb −1 . The discovery potential will be greatly enhanced with the full energy of s = 14 TeV .