The Matrix Method for Estimating the Background Induced by the Misidentification of a Jet as a Photon in pp Collider Experiment

This paper discusses the matrix method, which is an approach to the estimation of the background induced by the misidentification of a hadronic jet as a photon. To obtain the number of such background events the method uses the efficiencies of real/fake photons to pass the identification criteria. Selected events are categorized based on the photon isolation. The number of $${\text{jet}} \to \gamma $$ background events in the region of interest can be estimated using the auxiliary region. The proposed method does not require any optimization procedure in order for its correct application, which is an advantage over other commonly used approaches.