The 750 GeV Diphoton Excess as a First Light on Supersymmetry Breaking

TL;DR

This paper investigates how sgoldstino decays in low-energy supersymmetry-breaking models could explain the 750 GeV diphoton excess, exploring mechanisms to match the observed resonance width and mass splitting.

Contribution

It proposes new methods to enhance sgoldstino decay width and introduces an efficient mechanism for scalar-pseudoscalar mass splitting, advancing supersymmetry-based explanations for the excess.

Findings

Enhanced sgoldstino width via decay into Higgses and Higgsinos.

A novel mechanism for scalar-pseudoscalar mass splitting.

Potential to explain the observed diphoton resonance width.

Abstract

One of the most exciting explanations advanced for the recent diphoton excess found by ATLAS and CMS is in terms of sgoldstino decays: a signal of low-energy supersymmetry-breaking scenarios. The sgoldstino, a scalar, couples directly to gluons and photons, with strength related to gaugino masses, that can be of the right magnitude to explain the excess. However, fitting the suggested resonance width, Gamma ~ 45 GeV, is not so easy. In this paper we explore efficient possibilities to enhance the sgoldstino width, via the decay into two Higgses, two Higgsinos and through mixing between the sgoldstino and the Higgs boson. In addition, we present an alternative and more efficient mechanism to generate a mass splitting between the scalar and pseudoscalar components of the sgoldstino, which has been suggested as an interesting alternative explanation to the apparent width of the resonance.