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Renormalization Scale-Fixing for Complex Scattering Amplitudes

Stanley J. Brodsky·Felipe J. Llanes-Estrada
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Abstract

We show how to fix the renormalization scale for hard-scattering exclusive processes such as deeply virtual meson electroproduction by applying the BLM prescription to the imaginary part of the scattering amplitude and employing a fixed-t dispersion relation to obtain the scale-fixed real part. In this way we resolve the ambiguity in BLM renormalization scale-setting for complex scattering amplitudes. We illustrate this by computing the H generalized parton distribution at leading twist in an analytic quark-diquark model for the parton-proton scattering amplitude which can incorporate Regge exchange contributions characteristic of the deep inelastic structure functions.

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Stanley J. Brodsky, Felipe J. Llanes-Estrada. 2006-03-16. Renormalization Scale-Fixing for Complex Scattering Amplitudes. https://doi.org/10.1140/epjc%2Fs2006-02520-0

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