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One Loop Multiphoton Helicity Amplitudes

Gregory Mahlon
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Abstract

We use the solutions to the recursion relations for double-off-shell fermion currents to compute helicity amplitudes for $n$-photon scattering and electron-positron annihilation to photons in the massless limit of QED. The form of these solutions is simple enough to allow {\it all}\ of the integrations to be performed explicitly. For $n$-photon scattering, we find that unless $n=4$, the amplitudes for the helicity configurations (+++...+) and (-++...+) vanish to one-loop order.

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Gregory Mahlon. 1993-11-02. One Loop Multiphoton Helicity Amplitudes. https://doi.org/10.1103/physrevd.49.2197

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