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Physical Review D

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Two-photon effects in lepton-antilepton pair photoproduction from a nucleon target using real photons

Pervez Hoodbhoy

Department of Physics Quaid-e-Azam University Islamabad 45320 Pakistan

Phys. Rev. D 73, 054027 – Published 30 March, 2006

DOI: https://doi.org/10.1103/PhysRevD.73.054027

Abstract

We consider the production of a lepton-antilepton pair by real photons off a hadronic target. The interference of one and two-photon exchange amplitudes leads to a charge asymmetry term that may be calculated explicitly in the large- $t$ limit in terms of hadronic distribution amplitudes. A rather compact expression emerges for the leading order asymmetry at fixed angle in the center-of-mass of the lepton pair. The magnitude appears sizeable and is approximately independent of the pair mass in the asymptotic limit.

Article Text

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