Flavor Changing Heavy Higgs Interactions with Leptons at Hadron Colliders

In a general two Higgs doublet model, we study flavor changing neutral Higgs (FCNH) decays into leptons at hadron colliders, $pp \to \phi^0 \to \tau^\mp\mu^\pm +X$,where$\phi^0$couldbeaCP-evenscalar($h^0$,$H^0$) or a CP-odd pseudoscalar ($A^0$). The light Higgs boson $h^0$ is found to resemble closely the Standard Model Higgs boson at the Large Hadron Collider. In the alignment limit of $\cos (\beta -\alpha )\cong 0$ for $h^0$–$H^0$ mixing, FCNH couplings of $h^0$ are naturally suppressed, but such couplings of the heavier $H^0,A^0$ are sustained by $\sin (\beta -\alpha )\simeq 1$. We evaluate physics backgrounds from dominant processes with realistic acceptance cuts and tagging efficiencies. We find promising results for $\sqrt{s}=14$ TeV, which we extend further to $\sqrt{s}=27$ TeV and 100 TeV future pp colliders.