Measuring the top-quark Yukawa coupling at hadron colliders viatt¯h,h→W+W−

We study the signal and backgrounds for the process $t\overline{t}h,\overrightarrow{h}{W}^{+}{W}^{-}$ at the CERN Large Hadron Collider (LHC) and a 100 TeV Very Large Hadron Collider (VLHC). Signals are studied in two-, three-, and four-lepton final states. We find a statistical uncertainty in the top-quark Yukawa coupling at the LHC of $16\%,8\%,12\%$ for $m_h=130,160,190\mathrm{}\hspace{0.5em}\mathrm{GeV},$ respectively. The statistical uncertainty at the VLHC is likely to be negligible in comparison with the systematic uncertainty.