First constraints on invisible Higgs boson decays using $\mathrm{t}\bar{\mathrm{t}}\mathrm{H}$ production at $\sqrt{s}=13~\mathrm{TeV}$

This document presents first upper bounds on the branching fraction of the Higgs boson to invisible particles using an event topology corresponding to production of the Higgs boson in association with a top quark pair. This is done by reinterpreting results of the searches for scalar top quarks performed in the all-hadronic, the semi-leptonic, and the di-leptonic final states. Proton-proton collision data at $\sqrt{s}=13~\mathrm{TeV}$ is used, recorded with the CMS detector at the CERN Large Hadron Collider in 2016 and corresponding to an integrated luminosity of $35.9~\mathrm{fb}^{-1}$. An observed (expected) upper limit of $\mathcal{B}(\mathrm{H}\to\mathrm{inv})<0.46 \left(0.48\right)$ is set on the branching fraction of the Higgs boson decaying to invisible particles at the $95\%$ confidence level, assuming standard model $\mathrm{t}\bar{\mathrm{t}}\mathrm{H}$ production cross section.