Abstract
AbstractWe analyse effective potential around the electroweak (EW) scale in the Standard Model (SM) extended with a heavy scalar doublet. We show that the additional scalars can have a strong impact on vacuum stability. Although the additional heavy scalars may improve the behaviour of running Higgs self-coupling at large field values, we prove that they can destabilise the vacuum due to EW-scale effects. A new EW symmetry conserving minimum of the effective potential can appear rendering the electroweak symmetry breaking (EWSB) minimum meta- or unstable. However, for the case of the inert doublet model (IDM) with a 125 GeV Higgs boson we demonstrate that the parameter space region where the vacuum is meta- or unstable cannot be reconciled with the constraints from perturbative unitarity, electroweak precision tests (EWPT) and dark matter relic abundance measurements.
Highlights
That in the inert doublet model (IDM) the potential is stable up to higher energy scales than the Standard Model (SM) potential [25, 27]
In this work we analysed the impact of new scalar particles on the structure of effective potential of the IDM around the EW scale
They can turn the maximum of the effective potential at φ = 0 into a minimum, and change the energy of the electroweak symmetry breaking (EWSB) minimum in such a way that it becomes only a local one
Summary
That in the IDM the potential is stable up to higher energy scales than the SM potential [25, 27]. This is, not enough for stability of the EWSB vacuum since the additional scalars can modify the structure of the effective potential introducing new minima, potentially deeper than the EWSB minimum. The aim of the present article is to examine the structure of the potential and stability of the vacuum state around the EW scale in the presence of inert scalars. Scalar interactions of two SU(2) doublets in the IDM are given by the following potential m211(φ†S φS ) + m222(φ†DφD). To preserve it Yukawa interactions are set to type I (i.e. only the φS doublet couples to fermions), and at tree level a D-symmetric vacuum state is considered φS
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
