Infrared-finite factorization and renormalization scheme for exclusive processes. Application to pion form factors

1998/12/08 by N. G. Stefanis, Stefanis, N. G., W. Schroers +4
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-ph

paper · pdf · doi:10.48550/arxiv.hep-ph/9812280

23 pages, RevTeX is used. Four figures in PS files

arxiv created 1998/12/08 · openalex publication_date 1998/12/08 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

We develop and discuss an infrared-finite factorization and optimized renormalization scheme for calculating exclusive processes which enables the inclusion of transverse degrees of freedom without entailing suppression of calculated observables, like form factors. This is achieved by employing an analytic, i.e., infrared stable, effective coupling α_s(Q²) which removes the Landau singularity at Q²=Λ_{\rm QCD}² by a power-behaved correction. The ensuing contributions to the cusp anomalous dimension, related to the Sudakov form factor, and to the quark anomalous dimension, which controls evolution, lead to enhancement of the hard part of exclusive amplitudes, calculated in perturbative QCD. The phenomenological implications of this framework are analyzed by applying it to the pion's electromagnetic form factor and the pion-photon transition.

Related

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