Next-to-Leading Order Unitarity Fits in the Extended Georgi-Machacek Model

Chowdhury, Debtosh; Mondal, Poulami; Samanta, Subrata

Next-to-Leading Order Unitarity Fits in the Extended Georgi-Machacek Model

Apr 29, 2024

58 pages

e-Print:

2404.18996 [hep-ph]

View in:

ADS Abstract Service

pdf

reference search6 citations

Citations per year

Abstract: (arXiv)

Minimal triplet scalar extension of the Standard Model demanding custodial symmetry gives rise to the extended Georgi-Machacek (eGM) model. We compute one-loop corrections to all

2 \rightarrow 2

bosonic scattering amplitudes in the eGM model, and place next-to-leading order (NLO) unitarity bounds on the quartic couplings. Additionally, we derive state-of-the-art constraints on the quartic couplings demanding the stability of the scalar potential. We perform a global fit of the eGM model to these theoretical bounds and to the latest Higgs signal strength results from the LHC detectors. In addition to the custodial symmetry, imposing a global

SU(2)_L\otimes SU(2)_R

symmetry on the scalar potential at the electroweak scale results in the well-known Georgi-Machacek (GM) model. We assess the impact of the state-of-the-art theoretical constraints on the fit to the Higgs signal strength data in the GM model, with particular emphasis on the NLO unitarity bounds. We observe that the global fit disfavors the region where

\kappa_V

is greater than

1.05

with a 95.4% confidence level. We obtain an upper limit on the absolute values of the quartic couplings to be 1.9 (4.2) and see that the absolute mass differences between the heavy Higgs bosons cannot exceed 400 GeV (380 GeV) in the GM (eGM) model. Finally, we find that the maximal mass splitting within the members of custodial symmetric multiplets is restricted to be smaller than 210 GeV in the eGM model.

Note:

58 pages, 13 figures. Comments are welcome

potential: scalar
symmetry: custodial
higher-order: 1
Higgs particle: heavy
boson: scattering amplitude
scale: electroweak interaction
model: minimal
triplet: scalar
GeV
unitarity

References(90)

Figures(13)

[1]

Observation of a new particle in the search for the Standard Model Higgs boson with the ATLAS detector at the LHC

ATLAS

Collaboration

•

Georges Aad
(
- Freiburg U.
)

et al.

- Phys.Lett.B 716 (2012) 1-29
•
e-Print:
- 1207.7214
•
DOI:
- 10.1016/j.physletb.2012.08.020

[2]

Observation of a New Boson at a Mass of 125 GeV with the CMS Experiment at the LHC

CMS

Collaboration

•

Serguei Chatrchyan
(
- Yerevan Phys. Inst.
)

et al.

- Phys.Lett.B 716 (2012) 30-61
•
e-Print:
- 1207.7235
•
DOI:
- 10.1016/j.physletb.2012.08.021

[3]

Measurements of the Higgs boson production and decay rates and constraints on its couplings from a combined ATLAS and CMS analysis of the LHC pp collision data at $\sqrt{s}=7$ and 8 TeV

ATLAS and
CMS

Collaborations

•

Georges Aad
(
- Marseille, CPPM
)

et al.

- JHEP 08 (2016) 045
•
e-Print:
- 1606.02266
•
DOI:
- 10.1007/JHEP08(2016)045

[4]

Measurement of the properties of Higgs boson production at $\sqrt{s} = 13$ TeV in the $H\to\gamma\gamma$ channel using $139$ fb $^{-1}$ of $pp$ collision data with the ATLAS experiment

ATLAS

Collaboration

•

Georges Aad
(
- Marseille, CPPM
)

et al.

- JHEP 07 (2023) 088
•
e-Print:
- 2207.00348
•
DOI:
- 10.1007/JHEP07(2023)088

[5]

Higgs boson production cross-section measurements and their EFT interpretation in the $4\ell$ decay channel at $\sqrt{s}=$ 13 TeV with the ATLAS detector

ATLAS

Collaboration

•

Georges Aad
(
- Marseille, CPPM
)

et al.

- Eur.Phys.J.C 80 (2020) 10, 957,
- Eur.Phys.J.C 81 (2021) 1, 29 (erratum),
- Eur.Phys.J.C 81 (2021) 5, 398 (erratum)
•
e-Print:
- 2004.03447
•
DOI:
- 10.1140/epjc/s10052-020-8227-9