Measurements of $H\to W^{+}{W}^{-}$ in the Fully Leptonic Decay Mode at the FCC-ee

The expected precision on measuring the $\sigma (e^{+}{e}^{-}\to ZH)\times Br(H\to W^{+}{W}^{-})$ in the fully leptonic decay mode at the Future Circular Collider (FCC) is presented. We consider two FCC-ee scenarios: $\sqrt{s}=240$ GeV centre-of-mass energy with a luminosity of 10.8${\mathrm{a}\mathrm{b}}^{-1}$ and $\sqrt{s}=365$ GeV centre-of-mass energy with a luminosity of 3.12${\mathrm{a}\mathrm{b}}^{-1}$. Our results indicate that a relative uncertainty of 2.9% and 6.8% can be achieved on measurements of $\sigma (e^{+}{e}^{-}\to ZH)\times Br(H\to W^{+}{W}^{-})$ in the fully leptonic decay mode at $\sqrt{s}=240$ GeV and $\sqrt{s}=365$ GeV, respectively.