Abstract
The exclusive photoproduction off nucleon of a large invariant mass lepton pair in the backward region specified by the small Mandelstam variable -u is discussed in the framework of collinear QCD factorization. The amplitude is factorized in terms of photon-to-nucleon Transition Distribution Amplitudes (TDAs). These new non-perturbative objects, complementary to the “photon-inside-the-nucleon PDF”, lead to a tomographic picture of the nucleon’s photon content after Fourier transforming to the impact parameter space. This allows to address the question of where in the transverse plane the nucleon emits a photon. A simplistic model-estimate of photon-to-nucleon TDAs is used to estimate the magnitude of the corresponding cross sections. The background due to the electromagnetic Bethe–Heitler process is shown to be negligible in the kinematical regime of interest.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
