Measuring the Photon Fragmentation Function at HERA

Abstract

The production of final state photons in deep inelastic scattering originates from photon radiation off leptons or quarks involved in the scattering process. Photon radiation off quarks involves a contribution from the quark-to-photon fragmentation function, corresponding to the non-perturbative transition of a hadronic jet into a single, highly energetic photon accompanied by some limited hadronic activity. Up to now, this fragmentation function was measured only in electron-positron annihilation at LEP. We demonstrate by a dedicated parton-level calculation that a competitive measurement of the quark-to-photon fragmentation function can be obtained in deep inelastic scattering at HERA. Such a measurement can be obtained by studying the photon energy spectra in $\gamma +(0+1)$-jet events, where $\gamma$ denotes a hadronic jet containing a highly energetic photon (the photon jet). Isolated photons are then defined from the photon jet by imposing a minimal photon energy fraction. For this so-called democratic clustering approach, we study the cross sections for isolated $\gamma +(0+1)$-jet and $\gamma +(1+1)$-jet production as well as for the inclusive isolated photon production in deep inelastic scattering.

23 pages, LaTeX

References in corpus (21)

• New Generation of Parton Distributions with Uncertainties from Global QCD Analysis
• High-Energy-Physics Event Generation with PYTHIA 6.1
• Successive Combination Jet Algorithm For Hadron Collisions
• Isolated photons in perturbative QCD
• Parton distributions incorporating QED contributions
• Cross section of isolated prompt photons in hadron-hadron collisions
• Measurement and QCD Analysis of Jet Cross Sections in Deep-Inelastic Positron-Proton Collisions at sqrt(s) of 300 GeV
• A complete $\mathcal{O}(\alpha {\alpha }_s)$ calculation of the Photon + 1 Jet rate in $e^{+}{e}^{-}$ annihilation
• Quarks and Gluon Fragmentation Functions into Photons
• QED Radiative Corrections for Parton Distributions
• Beyond leading order effects in photon pair production at the Tevatron
• Measurement of inclusive prompt photon photoproduction at HERA
• Measurement of the quark to photon fragmentation function through the inclusive production of prompt photons in hadronic Z^0 decays
• Radiative Corrections to the Photon + 1 Jet Rate at LEP
• Observation of isolated high-E_T photons in deep inelastic scattering
• Isolated Photons in Deep Inelastic Scattering
• Dijet Production in Charged and Neutral Current e^+p Interactions at High Q^2
• Delineating the polarized and unpolarized photon distributions of the nucleon in eN collisions
• Final state photon production at LEP
• Photon Plus Jet Production in Large-Q2 ep Collisions at Next-to-Leading Order QCD
• Photon Fragmentation in Large-Q2 ep Collisions at Next-to-Leading Order QCD

Cited by in corpus (20)

• Parton Fragmentation Functions
• CT14QED PDFs from Isolated Photon Production in Deep Inelastic Scattering
• Electroweak corrections to hadronic production of W bosons at large transverse momenta
• Hadron Fragmentation Inside Jets in Hadronic Collisions
• The Hadronic Final State at HERA
• Measurement of isolated photon production in deep inelastic ep scattering
• The photon PDF of the proton
• Photon isolation effects at NLO in gamma gamma + jet final states in hadronic collisions
• Electroweak corrections to hadronic event shapes and jet production in e+e- annihilation
• Inclusive prompt photon-jet correlations as a probe of gluon saturation in electron-nucleus scattering at small $x$
• Measurement of Isolated Photon Production in Deep-Inelastic Scattering at HERA
• Isolated photon and photon+jet production at NNLO QCD accuracy
• Access to Photon Fragmentation Functions in Hadronic Jet Production
• Measurement of isolated photons accompanied by jets in deep inelastic ep scattering
• Single Photon Production at Hadron Colliders at NNLO QCD with Realistic Photon Isolation
• NLO Calculation of Prompt Photon Production in DIS at HERA
• Probing the polarized photon content of the proton in $ep$ collisions at the EIC
• Prompt photon production in photoproduction, DIS and hadronic collisions
• Photon production in Pb+Pb collisions at $\sqrt{s_{NN}}$=2.76 TeV
• QCD Physics with ZEUS and H1 at HERA