Perturbativity, vacuum stability and inflation in the light of 750 GeV diphoton excess

TL;DR

This paper investigates models explaining the 750 GeV diphoton excess, focusing on their perturbativity, vacuum stability, and inflation potential, and finds conditions for these models to remain weakly coupled up to the Planck scale.

Contribution

It introduces a simple model with colored vector-like fermions that remains weakly coupled up to the Planck scale and analyzes its stability and inflation prospects.

Findings

Models explaining the excess can stay perturbative up to the Planck scale with suitable parameters.

Conditions for vacuum stability are derived for the proposed scenario.

The potential for inflation within this framework is discussed.

Abstract

The recent observation of the 750 GeV diphoton excess at 13 TeV LHC has motivated many scenarios of physics beyond the Standard Model. In this work, we begin by showing that many models which explain the observed excess tend to get strongly coupled well below the Planck scale. We then study a simple scenario involving colored vector-like fermions with exotic charges, which is expected to stay weakly coupled till the Planck scale. We find the conditions under which this happens, derive the Renormalization Group equations for such models and solve them to show that perturbativity till Planck scale can be maintained for a very reasonable choice of parameters. Finally, we discuss issues related to vacuum stability and the possibility of inflation in the scenarios we study.