Title
Subleading power corrections to the pion-photon transition form factor in QCD
Author
Yue-Long Shen
College of Information Science and Engineering, Ocean University of China
Abstract
We reconsider QCD factorization for the leading power contribution to the γ*γ → π0 form factor Fγ*γ→π0(Q2) at one loop using the evanescent operator approach, and demonstrate the equivalence of the resulting factorization formulae derived with distinct prescriptions of γ5 in dimensional regularization. Applying the light-cone QCD sum rules (LCSRs) with photon distribution amplitudes (DAs) we further compute the subleading power contribution to the pion-photon form factor induced by the “hadronic” component of the real photon at the next-to-leading-order in O(αs), with both naive dimensional regularization and ’t Hooft-Veltman schemes of γ5. Confronting our theoretical predictions of Fγ*γ→π0 (Q2) with the experimental measurements from the BaBar and the Belle Collaborations implies that a reasonable agreement can be achieved without introducing an “exotic” end-point behaviour for the twist-2 pion DA.
Keywords
Perturbative QCDResummation
Object type
Language
English [eng]
Persistent identifier
Appeared in
Title
Journal of High Energy Physics
Volume
2017
Issue
12
Publication
Springer Nature
Version type
Date issued
2017
Access rights
Rights
Rights statement
© The Author(s) 2017
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