Scattering Light by Light at 750 GeV at the LHC

TL;DR

This paper explores a minimal scalar resonance model at 750 GeV produced via photon fusion, capable of explaining the diphoton excess and predicting related signals, with potential verification through light-by-light scattering measurements.

Contribution

It introduces a minimal effective coupling model for the 750 GeV resonance, linking it to new vectorlike fermions and proposing experimental tests via forward proton detectors.

Findings

Model reproduces the observed diphoton rate and width.

Predicts signals in WW, ZZ, Zγ channels.

Compatible with existing 8 TeV limits.

Abstract

We consider the possibility that the diphoton excess at 750 GeV is caused by a new scalar resonance produced in photon fusion. This scenario is parametrised by only one relevant effective couplings and is thus minimal. We show that this setup can reproduce both the production rate and width of the resonance, and is not in conflict with the 8 TeV limits on the diphoton cross section. The scenario also predicts event rates for $WW$, $ZZ$, $Z\gamma$ final states. We suggest to perform precision measurements by studying light-by-light scattering with intact protons detected in forward detectors. We construct a simple model that shows that the required couplings can be achieved with new vectorlike, uncolored fermions (with a strong Yukawa coupling to the resonance) which may also account for the required width.