A method based on transverse energy balance of jets for selection of direct photons and fragmentation photons in high energy pp collisions

TL;DR

This paper introduces a new jet transverse energy balance method to enhance direct photon detection in high energy proton-proton collisions, effectively reducing background fragmentation photons by 35% despite a slight efficiency decrease.

Contribution

The paper presents a novel approach based on jet transverse energy balance to distinguish direct photons from fragmentation backgrounds in pp collisions.

Findings

Rejects 35% of fragmentation photon background

Reduces direct photon detection efficiency by 10%

Provides a new tool for photon identification in high energy physics

Abstract

Direct photons are important probes in high energy collisions. They play an important role in determining the parton distribution function directly inside a proton as well as the nature of the matter formed in heavy ion collisions. However fragmentation photons play the role of prominent background in identifying the direct photons. In the present work we developed a new method based on the transverse energy balance of jets for enrichment of direct photon candidates in pp collisions. This method can reject 35% of the background photons (fragmentation) which can not be suppressed by isolation. Efficiency of detection of direct photon decrease by 10% in the method.