Subleading power corrections to the pion-photon transition form factor in QCD

Autor(en)

Yu-Ming Wang, Yue-Long Shen

Abstrakt

We reconsider QCD factorization for the leading power contribution to the γ

^*γ → π

⁰ form factor F0(Q

²) at one loop using the evanescent operator approach, and demonstrate the equivalence of the resulting factorization formulae derived with distinct prescriptions of γ

₅ 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(α

_s) , with both naive dimensional regularization and ’t Hooft-Veltman schemes of γ

₅. Confronting our theoretical predictions of F

₀ (Q

²) 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.

Organisation(en)

Teilchenphysik

Externe Organisation(en)

Nankai University, Ocean University of China

Journal

Journal of High Energy Physics

Band

2017

Anzahl der Seiten

38

ISSN

1029-8479

DOI

https://doi.org/10.1007/JHEP12(2017)037

Publikationsdatum

12-2017

Peer-reviewed

Ja

ÖFOS 2012

103012 Hochenergiephysik

Schlagwörter

ASJC Scopus Sachgebiete

Nuclear and High Energy Physics

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/c94fb478-936b-4111-b714-bdd3d64c583f