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Two-Photon Effects in Lepton-AntiLepton Pair Photoproduction from a Nucleon Target using Real Photons

Pervez Hoodbhoy
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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 centre-of-mass of the lepton pair. The magnitude appears sizeable and is approximately independent of the pair mass in the asymptotic limit.

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Pervez Hoodbhoy. 2006-03-05. Two-Photon Effects in Lepton-AntiLepton Pair Photoproduction from a Nucleon Target using Real Photons. https://doi.org/10.1103/physrevd.73.054027

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