Revisiting the factorization theorem for $\rho {\gamma }^{\ast }\to \pi (\rho )$ at twist 3

Abstract

We revisit the proof of the perturbative QCD factorization for the exclusive processes $\rho {\gamma }^{\star }\to \pi (\rho )$ at the two-parton twist-3 level. It is pointed out that the residual collinear divergences observed in the literature, which break the factorization of the above processes at the considered accuracy, are attributed to the improper insertion of the Fierz identity for factorizing the fermion flow. We show that the factorization theorem indeed holds at the two-parton twist-3 level after the mishandling is corrected.

7 pages, 2 figures, Accepted for publication in Physical Review D

References in corpus (2)

• The perturbative QCD factorization of $\rho {\gamma }^{\star }\to \pi$
• The perturbative QCD factorization of $\rho {\gamma }^{\star }\to \rho$

Cited by in corpus (4)

• The PQCD approach towards to next-to-leading order: a short review
• Rho-pion transition form factors in the $k_T$ factorization formulism revisited
• The next-to-leading order corrections to $B\to \rho$ transition in the $k_T$ factorization
• The next-to-leading order corrections to rho meson electromagnetic form factors in the $k_T$ factorization approach