Higgs Physics at the CLIC Electron-Positron Linear Collider

TL;DR

This paper evaluates CLIC's potential for precise Higgs boson measurements across three energy stages, highlighting its capability to probe Higgs couplings, self-coupling, and related new physics with high accuracy.

Contribution

It provides the first comprehensive analysis of Higgs physics reach at CLIC at multiple energy stages, including detailed sensitivity studies and global fit interpretations.

Findings

High-precision measurements of Higgs production cross sections.

Constraints on Higgs total decay width and couplings.

Potential to measure Higgs self-coupling and top Yukawa coupling.

Abstract

The Compact Linear Collider (CLIC) is an option for a future e+e- collider operating at centre-of-mass energies up to 3 TeV, providing sensitivity to a wide range of new physics phenomena and precision physics measurements at the energy frontier. This paper is the first comprehensive presentation of the Higgs physics reach of CLIC operating at three energy stages: sqrt(s) = 350 GeV, 1.4 TeV and 3 TeV. The initial stage of operation allows the study of Higgs boson production in Higgsstrahlung (e+e- -> ZH) and WW-fusion (e+e- -> Hnunu), resulting in precise measurements of the production cross sections, the Higgs total decay width Gamma_H, and model-independent determinations of the Higgs couplings. Operation at sqrt(s) > 1 TeV provides high-statistics samples of Higgs bosons produced through WW-fusion, enabling tight constraints on the Higgs boson couplings. Studies of the rarer processes e+e- -> ttH and e+e- -> HHnunu allow measurements of the top Yukawa coupling and the Higgs boson self-coupling. This paper presents detailed studies of the precision achievable with Higgs measurements at CLIC and describes the interpretation of these measurements in a global fit.