Projections of H$\to\tau\tau$ cross-section at FCC-ee

TL;DR

This paper assesses the projected precision of Higgs to tau-tau decay measurements at the FCC-ee collider, highlighting improved sensitivity over current LHC results and exploring tau reconstruction methods.

Contribution

It provides detailed projections for H→ττ cross-section measurements at FCC-ee and evaluates tau decay reconstruction techniques to maximize physics potential.

Findings

Projected measurement precision exceeds current LHC sensitivity by at least an order of magnitude.

Evaluation of tau decay reconstruction methods enhances analysis capabilities.

Results demonstrate FCC-ee's strong potential for Higgs property studies in the tau channel.

Abstract

The Future Circular Collider (FCC) stands at the forefront of the European Strategy for Particle Physics as the future flagship project at CERN. The H$\to\tau\tau$ decay, featuring a large branching ratio, clean identification in the FCC-ee environment, and the possibility to reconstruct polarization information, is an excellent channel to measure Higgs boson properties. This work shows the expected precision for the H$\to\tau\tau$ cross-section measurement at the FCC-ee in the ZH production mechanism at $\sqrt{s}=$240 GeV and $\sqrt{s}=$365 GeV, as well as via the vector boson fusion process at $\sqrt{s}=$365 GeV. Furthermore, we explore and evaluate a set of methods for reconstructing tau decays. These techniques are critical for unlocking the full physics potential of the FCC-ee and for improving the understanding of tau-related observables in both Standard Model measurements and New Physics searches. The results obtained significantly enhance the FCC-ee outlook in the H$\to\tau\tau$ channel, improving it by at least an order of magnitude compared to the current sensitivity of measurements' performance at the LHC.