Tau lepton reconstruction at the Muon Collider: Cross section measurement of the $H\rightarrow\tau^+\tau^-$ process

TL;DR

This study estimates the statistical uncertainty in measuring the Higgs to tau tau cross section at a 10 TeV Muon Collider, using the TauFinder algorithm for tau reconstruction, achieving 1.3% uncertainty.

Contribution

It introduces a method to reconstruct tau leptons at a Muon Collider and quantifies the expected measurement precision of the Higgs to tau tau process.

Findings

TauFinder achieves over 80% efficiency for 1-prong tau decays.

The statistical uncertainty on the cross section measurement is 1.3%.

The analysis compares Muon Collider sensitivities with other future colliders.

Abstract

Studies of Higgs boson properties are crucial for the understanding the Standard Model (SM), as it could couple to new particles and provide hints to physics Beyond the Standard Model (BSM). Different future colliders are proposed, among them the Muon Collider project would allow to perform unprecedented precision measurements of the Higgs boson parameters. The goal of this study is to estimate the statistical uncertainty of the cross section of the $H\rightarrow\tau^+\tau^-$ process at a 10 TeV center-of-mass energy Muon Collider. In order to reconstruct $\tau$ leptons in different decay modes, the TauFinder algorithm is used. The efficiency of hadronic $\tau$ ($\tau_h$) lepton identification is estimated to be above 80% for 1-prong and 50% for 3-prong decay modes. This study focuses on the signal process $H\rightarrow\tau^+\tau^-$ in which the $\tau$ leptons decay hadronically ($\tau_h$). The main background processes are discussed and compared with the signal. The visible invariant mass is reconstructed and template fits are performed with Monte Carlo toy experiments. A statistical uncertainty on the cross section of the signal process: $\Delta\sigma/\sigma=$1.3% is obtained. Finally, comparisons are made with the sensitivities at other future colliders, and possible improvements to the analysis are discussed.