Prospects for Measuring $H\to \rm{invisble}$ at the FCCee

TL;DR

This paper evaluates the potential of the FCCee collider to measure invisible Higgs decays via the ZH production mode at 240 GeV, projecting a 0.15% upper limit on the branching ratio.

Contribution

It provides a detailed sensitivity study for measuring invisible Higgs decays at the FCCee with specific decay channels and luminosity.

Findings

Projected 95% CL upper limit on BR(H→invisible) is 0.15%.

Analysis includes Z→ee, Z→μμ, and Z→jj decay modes.

Demonstrates FCCee's high sensitivity for Higgs invisible decay measurements.

Abstract

We present the prospects for measuring $H\to \rm{invisble}$ decays at the Future Circular Collider electron-positron at $\sqrt{s} = 240 \text{ GeV}$ with an integrated luminosity of 10.8 ab$^{-1}$. In this study, we consider the $ZH$ production mode with three decay modes of the $Z$ boson: $Z\to e^+e^-$, $Z\to \mu^+\mu^-$ and $Z\to jj$ ($b\bar{b}, c\bar{c}, s\bar{s}, q\bar{q}$). We find that at 95\% confidence limit, the combined upper limit on the $\mathcal{B}(H\to invisible)$ could reach 0.15\%.