Probing New Physics of Cubic Higgs Interaction via Higgs Pair Production at Hadron Colliders

TL;DR

This paper investigates how new physics affecting the cubic Higgs interaction can be probed through Higgs pair production at future hadron colliders, providing sensitivity estimates for measuring deviations from the Standard Model.

Contribution

It introduces a model-independent framework using dimension-6 operators to analyze cubic Higgs interactions via di-Higgs production at high-energy colliders, including detailed simulations and sensitivity studies.

Findings

The $gg\to hh \to b\bar{b}\gamma\gamma$ channel can measure the SM cubic Higgs coupling with about 13% accuracy at 14 TeV.

At 100 TeV collider, the same channel can achieve about 4.2% accuracy for the cubic Higgs coupling.

Sensitivity to derivative cubic Higgs coupling can reach about 1.6% at 100 TeV with high luminosity.

Abstract

Despite the discovery of a Higgs boson h(125GeV) at the LHC Run-1, its self-interaction has fully evaded direct experimental probe so far. Such self-interaction is vital for electroweak symmetry breaking, vacuum stability and electroweak phase transition, and Higgs inflation. It is a most likely place to encode new physics beyond the standard model. We parametrize such new physics by model-independent dimension-6 effective operators, and study their tests via Higgs pair production at hadron colliders. We analyze three major di-Higgs production channels at parton level, and compare the parameter-dependence of total cross sections and kinematic distributions at the LHC(14TeV) and pp(100TeV) hadron collider. We further perform full simulations for the di-Higgs production channel $gg\to hh \to b\bar{b}\gamma\gamma$ and its backgrounds at the pp(100TeV) hadron collider. We construct four kinds of benchmark points, and study the sensitivities to probing different regions of the parameter space of cubic Higgs interactions. We find that for one-parameter analysis and with a 3/ab (30/ab) integrated luminosity, the $gg\to hh \to b\bar{b}\gamma\gamma$ channel can measure the SM cubic Higgs coupling and the derivative cubic Higgs coupling to an accuracy of about 13% (4.2%) and 5% (1.6%), respectively.