Higgs Boson self-coupling measurements using ratios of cross sections

TL;DR

This paper proposes a method to measure the Higgs boson self-coupling at the LHC by analyzing the ratio of double-to-single Higgs production cross sections, reducing theoretical uncertainties and providing the most precise constraints to date.

Contribution

It introduces a novel approach using cross section ratios to constrain the Higgs self-coupling with reduced uncertainties, achieving high precision with large datasets.

Findings

Self-coupling can be constrained to be positive with 600/fb data at 95% CL.

Expected uncertainty on the self-coupling is about +30%/-20% with 3000/fb.

The method minimizes theoretical uncertainties compared to previous approaches.

Abstract

We consider the ratio of cross sections of double-to-single Higgs boson production at the Large Hadron Collider at 14 TeV. Since both processes possess similar higher-order corrections, leading to a cancellation of uncertainties in the ratio, this observable is well-suited to constrain the trilinear Higgs boson self-coupling. We consider the scale variation, parton density function uncertainties and conservative estimates of experimental uncertainties, applied to the viable decay channels, to construct expected exclusion regions. We show that the trilinear self-coupling can be constrained to be positive with a 600/fb LHC dataset at 95% confidence level. Moreover, we demonstrate that we expect to obtain a ~+30% and ~-20 uncertainty on the self-coupling at 3000/fb without statistical fitting of differential distributions. The present article outlines the most precise method of determination of the Higgs trilinear coupling to date.