Diphoton signals in theories with large extra dimensions to NLO QCD at hadron colliders

TL;DR

This paper calculates precise NLO QCD corrections for diphoton production at hadron colliders within the Standard Model and ADD large extra dimensions model, improving prediction stability and cross section estimates.

Contribution

It provides the first comprehensive NLO QCD analysis of diphoton signals in large extra dimensions theories at hadron colliders.

Findings

NLO corrections stabilize theoretical predictions.

Significant enhancement of diphoton production cross section.

Effective removal of fragmentation photons using smooth-cone-isolation.

Abstract

We present a full next-to-leading order (NLO) QCD corrections to diphoton production at the hadron colliders in both standard model and ADD model. The invariant mass and rapidity distributions of the diphotons are obtained using a semi-analytical two cut-off phase space slicing method which allows for a successful numerical implementation of various kinematical cuts used in the experiments. The fragmentation photons are systematically removed using smooth-cone-isolation cuts on the photons. The NLO QCD corrections not only stabilise the perturbative predictions but also enhance the production cross section significantly.