Constraints on the quartic Higgs self-coupling from double-Higgs production at future hadron colliders

We consider modifications of the Higgs potential due to new physics at high energy scales. These upset delicate cancellations predicted by the Standard Model for processes involving Higgs bosons and longitudinal gauge bosons, and lead to a breakdown of the theory at high energies. We focus on modifications of the Higgs trilinear coupling and use the violation of treelevel unitarity as an estimate of the scale where the theory breaks down. We obtain a completely model-independent bound of < ∼ 13 TeV for an order-1 modification of the trilinear. We argue that this bound can be saturated only in fine-tuned models, and the scale of new physics is likely to be much lower. The most stringent bounds are obtained from amplitudes involving multiparticle states that are not conventional scattering states. Our results show that a future determination of the Higgs cubic coupling can point to a well-defined scale of new physics that can be targeted and explored at future colliders.

Section: Introductionmentioning

confidence: 99%

The Higgs trilinear coupling and the scale of new physics

Chang

Luty

2020

“…(2.1). Of course this pattern changes once electroweak corrections, part of which have been calculated recently [29,67], are included. In order to allow for comparisons and cross checks, we implemented both the m t → ∞ limit as well as the amplitudes with full m t -dependence at NLO.…”

Section: Overview Of the Calculationmentioning

confidence: 99%

“…Recent phenomenological studies about the precision that could be reached for the trilinear coupling at the (HL-)LHC and future hadron colliders can be found for example in Refs. [26][27][28][29][30][31][32][33][34][35][36].…”

Section: Introductionmentioning

confidence: 99%

“…Measuring Higgs boson pair production is a direct way to access the trilinear Higgs coupling. The trilinear and quartic couplings can also be constrained in an indirect way, through measurements of processes which are sensitive to the Higgs boson self-couplings via electroweak corrections [29,[65][66][67][68][69][70][71][72][73][74][75][76][77]. Such processes offer important complementary information, however they are more susceptible to other BSM couplings entering the loop corrections at the same level, and therefore the limits on κ λ extracted this way may be more model dependent than the ones extracted from the direct production of Higgs boson pairs.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Probing the trilinear Higgs boson coupling in di-Higgs production at NLO QCD including parton shower effects

Heinrich

Jones

Kerner

et al. 2019

We present results for Higgs boson pair production with variations of the trilinear Higgs boson self coupling at next-to-leading order (NLO) in QCD including the full top quark mass dependence. Differential results for the LHC at 14 TeV are presented, and we discuss the implications of anomalous trilinear couplings as well as differences between the Pythia and Herwig parton showers in combination with POWHEG. The implementation of the NLO QCD calculation with variable Higgs boson self coupling is made publicly available in the POWHEG-BOX-V2 Monte Carlo framework. A simple method for using the new implementation to study also variations of the top quark Yukawa coupling is described.

“…Much remains to be understood about the Higgs sector. On the collider side, measuring the Higgs cubic and quartic couplings through double or triple Higgs production, both non-resonant as well as resonant, is an extremely difficult but central goal of future experiments (see e.g., [73][74][75][76][77][78][79]). While any deviation of the shape of the Higgs potential from what is expected within the Standard Model (SM) would hint to new physics, the sensitivities of such collider studies are found to be rather low.…”

Section: Introductionmentioning

confidence: 99%

Collider and gravitational wave complementarity in exploring the singlet extension of the standard model

Alves

Ghosh

Guo

et al. 2019

126

123

We present a dedicated complementarity study of gravitational wave and collider measurements of the simplest extension of the Higgs sector: the singlet scalar augmented Standard Model. We study the following issues: (i) the electroweak phase transition patterns admitted by the model, and the proportion of parameter space for each pattern; (ii) the regions of parameter space that give detectable gravitational waves at future space-based detectors; and (iii) the current and future collider measurements of di-Higgs production, as well as searches for a heavy weak diboson resonance, and how these searches interplay with regions of parameter space that exhibit strong gravitational wave signals. We carefully investigate the behavior of the normalized energy released during the phase transition as a function of the model parameters, address subtle issues pertaining to the bubble wall velocity, and provide a description of different fluid velocity profiles. On the collider side, we identify the subset of points that are most promising in terms of di-Higgs and weak diboson production studies while also giving detectable signals at LISA, setting the stage for future benchmark points that can be used by both communities.