A feasibility study of the measurement of Higgs pair creation at a Photon Linear Collider

TL;DR

This study assesses the potential to measure Higgs pair production at a Photon Linear Collider, identifying optimal collision energy and demonstrating the possibility of observing Higgs pairs with significant statistical confidence despite backgrounds.

Contribution

It provides a feasibility analysis for Higgs pair measurement at a PLC, including optimal energy and background suppression strategies, which is a novel assessment in this context.

Findings

Optimal gamma-gamma collision energy around 270 GeV for 120 GeV Higgs.

Higgs pair events can be observed with ~5 sigma significance in 5 years.

Background processes can be effectively suppressed with proper track assignment.

Abstract

We studied the feasibility of the measurement of Higgs pair creation at a Photon Linear Collider (PLC). From the sensitivity to the anomalous self-coupling of the Higgs boson, the optimum $\gamma \gamma$ collision energy was found to be around 270 GeV for a Higgs mass of 120 GeV/$c^2$. We found that large backgrounds such as $\gamma \gamma \rightarrow W^+W^-, ZZ,$ and $b\bar{b}b\bar{b}$, can be suppressed if correct assignment of tracks to parent partons is achieved and Higgs pair events can be observed with a statistical significance of $\sim 5 \sigma$ by operating the PLC for 5 years.