Probing anomalous tqh couplings via single top production in associated with the Higgs boson at the HE-LHC and FCC-hh

Abstract

AbstractWe investigate the prospects for discovering the Flavour Changing Neutral Current (FCNC) tqh couplings via the process $$pp\rightarrow th$$ p p → t h at the proposed High Energy Large Hadron Collider (HE-LHC) and Future Circular Collider in hadron-hadron mode (FCC-hh) including the realistic detector effects. The relevant SM backgrounds are considered in the cut based analysis to obtain the limits on the the branching ratios of $$t\rightarrow qh~(q=u,c)$$ t → q h ( q = u , c ) , followed by the leptonic decay channel of the top quark and diphoton decay channel of the Higgs boson. The upper limits on the FCNC branching ratios at 95% confidence level (CL) and the $$5\sigma $$ 5 σ discovery reach for the different integrated luminosities are obtained. It is shown that at the 27 TeV HE-LHC with an integrated luminosity of 15 ab$$^{-1}$$ - 1 and at the 100 TeV FCC-hh with an integrated luminosity of 30 ab$$^{-1}$$ - 1 , the BR($$t\rightarrow uh$$ t → u h ) (BR($$t\rightarrow ch$$ t → c h )) can be probed, respectively, to $$4.4~(6.4)\times 10^{-5}$$ 4.4 ( 6.4 ) × 10 - 5 and $$1.3~(1.6) \times 10^{-5}$$ 1.3 ( 1.6 ) × 10 - 5 at the 95% CL.