Effects of a Real Singlet Scalar on Veltman Condition

Abstract

We revisit the fine-tuning problem in the Standard Model (SM) and show the modification in Veltman condition by virtue of a minimally-extended particle spectrum with one real SM gauge singlet scalar field. We demand the new scalar to interact with the SM fields through Higgs portal only, and that the new singlet to acquire a vacuum expectation value, resulting in a mixing with the CP-even neutral component of the Higgs doublet in the SM. The experimental bounds on the mixing angle are determined by the observed best-fit signal strength $\sigma /{\sigma }_{\mathrm{SM}}$. While, the one-loop radiative corrections to the Higgs mass squared, computed with an ultraviolet cut-off scale $\Lambda$, comes with a negative coefficient, the quantum corrections to the singlet mass squared acquires both positive and negative values depending on the parameter space chosen, which if positive might be eliminated by introducing singlet or doublet vector-like fermions. However, based upon the fact that there is mixing between the scalars, when transformed into the physical states, the tree-level coupling of the Higgs field to the vector-like fermions worsen the Higgs mass hierarchy problem. Therefore, the common attempt to introduce vector-like fermions to cancel the divergences in the new scalar mass, might not be a solution, if there is mixing between the scalars.

6pp, 3 figs, accepted for publication in Physics Letters B

References in corpus (8)

• Observation of a new particle in the search for the Standard Model Higgs boson with the ATLAS detector at the LHC
• Observation of a new boson at a mass of 125 GeV with the CMS experiment at the LHC
• Gauge Singlet Scalars as Cold Dark Matter
• LHC Phenomenology of an Extended Standard Model with a Real Scalar Singlet
• Singlet Higgs Phenomenology and the Electroweak Phase Transition
• Complex Singlet Extension of the Standard Model
• The real singlet scalar dark matter model
• Just so Higgs boson

Cited by in corpus (5)

• Multi-Component Dark Matter in a Non-Abelian Dark Sector
• Effects of Curvature-Higgs Coupling on Electroweak Fine-Tuning
• Two component dark matter with multi-Higgs portals
• The hierarchy problem and the vacuum stability in two-scalar dark matter model
• Higgsed Stueckelberg Vector and Higgs Quadratic Divergence