Measuring the quartic Higgs self-coupling at a multi-TeV muon collider

M Chiesa,X Zhao,B Mele,F Maltoni,L Mantani,F Piccinini

doi:10.1007/jhep09(2020)098

Abstract

Measuring the shape of the Higgs boson potential is of paramount importance, and will be a challenging task at current as well as future colliders. While the expectations for the measurement of the trilinear Higgs self-coupling are rather promising, an accurate measurement of the quartic self-coupling interaction is presently considered extremely challenging even at a future 100 TeV proton-proton collider. In this work we explore the sensitivity that a muon collider with a center of mass energy in the multi-TeV range and luminosities of the order of 1035cm−2s−1, as presently under discussion, might provide, thanks to a rather large three Higgs-boson production and to a limited background. By performing a first and simple analysis, we find a clear indication that a muon collider could provide a determination of the quartic Higgs self-coupling that is significantly better than what is currently considered attainable at other future colliders.

Highlights

JHEP09(2020)098 where in the SM, λ3 = λ4 = m2H /2v2 ≡ λSM
In this work we explore the sensitivity that a muon collider with a center of mass energy in the multi-TeV range and luminosities of the order of 1035cm−2s−1, as presently under discussion, might provide, thanks to a rather large three Higgs-boson production and to a limited background
By performing a first and simple analysis, we find a clear indication that a muon collider could provide a determination of the quartic Higgs self-coupling that is significantly better than what is currently considered attainable at other future colliders

Summary

Triple Higgs production in the standard model

We present the cross sections and a few kinematical distributions for the process μ+μ− → HHH νν,. In order to compute the μ+μ− → HHHνν cross sections and distributions, including the complete self-coupling dependence, we have used two Monte Carlo event generators: Whizard [34, 35] (version 2.6.4) and MadGraph aMC@NLO [36]. The simplest instance is that of adding just one operator of dimension six, c6(Φ†Φ)3/Λ2 In this case, one finds that the shifts in the trilinear and quartic couplings are related, i.e., δ4 = 6 δ3, (SMEFT at dim = 6). One finds that the shifts in the trilinear and quartic couplings are related, i.e., δ4 = 6 δ3, (SMEFT at dim = 6) This constraint can be lifted by further adding operators of higher dimension, i.e., c8(Φ†Φ)4/Λ4. There is a very mild dependence on the collision energy

10 TeV 14 TeV

Triple Higgs production with anomalous self-couplings

Sensitivity to the Higgs self-coupling deviations

Findings

Conclusions