Standard Model Higgs boson pair production in the $(b\bar{b})(b\bar{b})$ final state

Abstract: Measuring the Higgs boson couplings as precisely as possible is one of the major goals of the High Luminosity LHC. We show that the $(b\bar{b})(b\bar{b})$ final state in Higgs boson pair production can be exploited in the boosted regime to give constraints on the trilinear Higgs boson self-coupling. In these exclusive phase space regions, novel jet substructure techniques can be used to separate the signal from the large QCD and electroweak backgrounds. New developments on trigger and b-tagging strategies for the upcoming LHC runs are necessary in order to reconstruct the Higgs bosons in boosted final states, where the trilinear self-coupling sensitivity is reduced. We find that using our approach one can set a limit for $\lambda \leq 1.2$ at $95 \%$ CL after $3000~\mathrm{fb}^{-1}$. As the signal-to-background ratio is small we propose a data-driven side-band analysis to improve on the coupling measurement.

Analysis of Higgs Boson Pair Production in the $(b\bar{b})(b\bar{b})$ Final State

This paper provides a detailed examination of Standard Model Higgs boson pair production, specifically in the $(b\bar{b})(b\bar{b})$ final state, a channel characterized by substantial theoretical and experimental challenges. The focus is on constraining the trilinear Higgs self-coupling, $\lambda$, which is critical for understanding the electroweak symmetry breaking mechanism. This inquiry is situated within the context of the High Luminosity Large Hadron Collider (HL-LHC), where high-energy proton-proton collisions serve as a fertile ground for studying rare processes and couplings like the Higgs self-couplings.

Summary and Methodology

The authors leverage novel jet substructure techniques to isolate the Higgs pair production signal from substantial quantum chromodynamics (QCD) and electroweak backgrounds, utilizing boosted regimes where the Higgs bosons manifest as highly collimated decay products. Specific methods such as the BDRS method and Shower Deconstruction are employed to enhance the discrimination power between signal and background. The focus is on the large background from $b\bar{b}b\bar{b}$ production, requiring innovative approaches to manage the low signal-to-background ratio.

Numerical Findings and Constraints

The paper reports that, for $\lambda$ at the Standard Model value, a constraint of $\lambda \leq 1.2$ at 95% confidence level is feasible after accumulating $3000~\mathrm{fb}^{-1}$ of data. This assumes the use of advanced selection and tagging techniques which improve the fidelity of jet reconstruction, such as requiring jets with a transverse momentum $p_T \geq 200$ GeV. The analysis also underscores the importance of implementing data-driven methods, such as side-band analysis, to further constrain uncertainties inherent in theoretical calculations.

Implications for Future Research

The exploration of $(b\bar{b})(b\bar{b})$ Higgs final states has significant implications in the field of particle physics, particularly in testing the robustness of the Standard Model and searching for potential new physics scenarios that may alter the perceived Higgs boson self-coupling. Moreover, improvements in trigger and $b$-tagging strategies are suggested to optimize the data collection and analysis processes. Such advancements are pivotal in ensuring that measurements are not just statistically significant but also systematically controlled.

Conclusion

The stringent conditions of the Higgs boson pair production study underscore the sophisticated experimental techniques and theoretical frameworks needed at the HL-LHC. The potential to achieve meaningful constraints on the Higgs trilinear self-coupling demonstrates the feasibility of using the $(b\bar{b})(b\bar{b})$ final state as a viable probe of Higgs physics, potentially opening avenues for exploring beyond-the-Standard-Model phenomena if deviations from expected results are observed. This research thus contributes to a deeper understanding of fundamental particle interactions, laying the groundwork for further explorations into the properties of the Higgs boson and the dynamics of the Higgs field.