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arXiv · 1604.07175

Access to Photon Fragmentation Functions in Hadronic Jet Production

Abstract

We argue that the process $pp \to (\text{jet} \gamma)X$, for which a photon is observed inside a fully reconstructed jet and is treated as part of the jet, offers new probes of the so far little known fragmentation functions for photons. We present a next-to-leading-order QCD calculation of the cross section for this process in the limit that the jet is relatively narrow. We also investigate the background resulting from the two-photon decay of neutral pions. We present numerical results relevant for possible measurements at the LHC and at RHIC. These suggest that $pp \to (\text{jet} \gamma)X$ should provide clean access to the photon fragmentation functions, provided an efficient suppression of the background is available in experiment.

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Tom Kaufmann, Asmita Mukherjee, Werner Vogelsang. 2016-04-25. Access to Photon Fragmentation Functions in Hadronic Jet Production. https://doi.org/10.1103/physrevd.93.114021

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