Measurement of Higgs decay to WW* in Higgsstrahlung at $\sqrt{s}$=500 GeV ILC and in WW-fusion at $\sqrt{s}$=3 TeV CLIC

TL;DR

This paper evaluates the precision of measuring the Higgs boson's decay to WW* at future colliders, specifically ILC at 500 GeV and CLIC at 3 TeV, using full detector simulations and advanced analysis techniques.

Contribution

It provides the first detailed simulation-based estimates of Higgs to WW* measurement accuracy at both ILC and CLIC, considering realistic experimental conditions.

Findings

Estimated statistical uncertainties for Higgs to WW* branching ratio at ILC and CLIC.

Demonstrated the effectiveness of multivariate analysis in event selection.

Quantified the impact of beam effects and backgrounds on measurement precision.

Abstract

This talk presents results of the two independent analyses evaluating the measurement accuracy of the branching ratio for the Standard model Higgs boson decay to a W-pair, at the Compact Linear Collider (CLIC) and at the International Linear Collider (ILC). The considered Higgs production channels are the WW-fusion for the highest energy stage of CLIC, $\sqrt{s}$= 3 TeV, and the Higgsstrahlung process for the nominal ILC energy, $\sqrt{s}$=500 GeV. Both studies are performed using the full simulation of the detector. The realistic experimental conditions have been simulated including beam energy spectrum, initial state radiation and the backround from $\gamma\gamma\rightarrow hadrons$ processes, which are overlaid on simulated events. The multivariate analysis technique is used for the final event selection and the expected relative statistical uncertainty, $\Delta (\sigma \cdot BR) / (\sigma\cdot BR)$, of the measured Higgs production cross sections is estimated.