Anomalous Couplings in Double Higgs Production

TL;DR

This paper evaluates the LHC's ability to detect non-standard Higgs interactions in double Higgs production, highlighting promising prospects for measuring the (ttbar hh) coupling, which signals new physics beyond the Standard Model.

Contribution

It provides a model-independent analysis of the LHC's potential to detect anomalous Higgs couplings, especially focusing on the (ttbar hh) interaction.

Findings

Sensitivity to the Higgs trilinear coupling is limited.

Potential to measure the (ttbar hh) coupling is promising.

Double Higgs production can reveal new physics signatures.

Abstract

The process of gluon-initiated double Higgs production is sensitive to non-linear interactions of the Higgs boson. In the context of the Standard Model, studies of this process focused on the extraction of the Higgs trilinear coupling. In a general parametrization of New Physics effects, however, an even more interesting interaction that can be tested through this channel is the (ttbar hh) coupling. This interaction vanishes in the Standard Model and is a genuine signature of theories in which the Higgs boson emerges from a strongly-interacting sector. In this paper we perform a model-independent estimate of the LHC potential to detect anomalous Higgs couplings in gluon-fusion double Higgs production. We find that while the sensitivity to the trilinear is poor, the perspectives of measuring the new (ttbar hh) coupling are rather promising.