Di-Higgs blind spots in gravitational wave signals

Alexandre Alves,Dorival Gonçalves,Tathagata Ghosh,Huai-Ke Guo,Kuver Sinha

doi:10.1016/j.physletb.2021.136377

Abstract

Conditions for strong first-order phase transition and generation of observable gravitational wave (GW) signals are very restrictive to the profile of the Higgs potential. Working in the minimal extension of the SM with a new gauge singlet real scalar, we show that the production of signals relevant for future GW experiments, such as LISA, can favor depleted resonant and non-resonant di-Higgs rates at colliders for phenomenologically relevant regimes of scalar mixing angles and masses for the heavy scalar. We perform a comprehensive study on the emergence of these di-Higgs blind spot configurations in GWs and also show that di-boson channels, ZZ and WW, can restore the phenomenological complementarities between GW and collider experiments in these parameter space regimes.

Highlights

The Higgs potential is a vital element of the Standard Model (SM) of particle physics
We carefully study the phenomenological conditions on the Higgs potential, as well as the parameters governing the observation of gravitational wave (GW), that restrict the Higgs sector to the blind spots
Using the xSM model as a template, we have shown that the production of signals relevant for future GW experiments can favor feeble h2h1h1 interactions and characteristic Higgs self-couplings in phenomenologically relevant sin θ and mh2 regimes

Summary

INTRODUCTION

The Higgs potential is a vital element of the Standard Model (SM) of particle physics. The significant characteristics of the effective potential are the relative depth of the true minimum, the height of the barrier that separates the true minimum from the false one, and the distance between the two minima in field space at the nucleation temperature [43] While this is an apparent simple picture, it has interesting phenomenological implications when the Higgs boson mixes with other scalars. We carefully study the phenomenological conditions on the Higgs potential, as well as the parameters governing the observation of GWs, that restrict the Higgs sector to the blind spots This includes a detailed exploration of the shape of the Higgs potential, in the vicinity of these parameter space regimes, through scrutiny of the Higgs couplings, potential barrier, potential depth, and the separation of the minima during the phase transition.

DI-HIGGS BLIND SPOTS

Scalar Potential

Emergence of Blind Spots

Gravitational Wave Production

SUMMARY