Higgs-to-Invisible Searches with the CMS experiment at the LHC

Abstract

Searches for invisible decays of the Higgs boson are presented using data at a centre-of-mass energy of $\sqrt{s} = 13~\text{TeV}$ collected with the CMS detector at the LHC in 2016. The dataset corresponds to an integrated luminosity of 35.9 \fb. The search channel targets Higgs boson production via vector boson fusion. The results are presented in terms of an upper limit on the branching fraction of the Higgs boson decay to invisible particles $\mathcal{B}(H\rightarrow \text{inv.})$. The data are in agreement with the contribution of backgrounds from standard model processes. An observed (expected) upper limit on $\mathcal{B}(H\rightarrow \text{inv.})$ at 95\% confidence level is set at 0.53 (0.27) for the cut-and-count and at 0.28 (0.21) for the shape approaches respectively. A combination with other relevant analyses to further improve the sensitivity to $\mathcal{B}(H\rightarrow \text{inv.})$ is also presented using the 2016 dataset. An observed (expected) upper limit on $\mathcal{B}(H\rightarrow \text{inv.})$ at 95\% confidence level is set at 0.24 (0.18), assuming standard model production rates. This result represents the most sensitive Higgs-to-invisible search, and it is interpreted in the context of Higgs-portal models for dark matter where upper bounds are placed on the dark matter-nucleon spin-independent cross-section.