Boosting Higgs pair production in the $b\bar{b}b\bar{b}$ final state with multivariate techniques

TL;DR

This paper evaluates the potential to observe Higgs pair production in the four-bottom-quark final state at the High-Luminosity LHC using advanced multivariate analysis techniques, accounting for complex backgrounds and pileup effects.

Contribution

It introduces a combined cut-based and multivariate analysis approach for Higgs pair production in the $b\bar{b}b\bar{b}$ channel, demonstrating feasibility at high luminosity.

Findings

Achieves a signal significance of about 3 with 3 ab$^{-1}$ luminosity.

Shows robustness of analysis in high pileup conditions.

Indicates potential for observing double Higgs production in this channel.

Abstract

The measurement of Higgs pair production will be a cornerstone of the LHC program in the coming years. Double Higgs production provides a crucial window upon the mechanism of electroweak symmetry breaking and has a unique sensitivity to the Higgs trilinear coupling. We study the feasibility of a measurement of Higgs pair production in the $b\bar{b}b\bar{b}$ final state at the LHC. Our analysis is based on a combination of traditional cut-based methods with state-of-the-art multivariate techniques. We account for all relevant backgrounds, including the contributions from light and charm jet mis-identification, which are ultimately comparable in size to the irreducible $4b$ QCD background. We demonstrate the robustness of our analysis strategy in a high pileup environment. For an integrated luminosity of $\mathcal{L}=3$ ab$^{-1}$, a signal significance of $S/\sqrt{B}\simeq 3$ is obtained, indicating that the $b\bar{b}b\bar{b}$ final state alone could allow for the observation of double Higgs production at the High-Luminosity LHC.