Three-parton contribution to pion form factor in kT factorization

Abstract

We set up a framework for the study of the power-suppressed three-parton contribution to the pion electromagnetic form factor in the $k_T$ factorization theorem. It is first shown that the gauge dependence proportional to parton transverse momenta from the two-parton Fock state and the gauge dependence associated with the three-parton Fock state cancel each other. After verifying the gauge invariance, we derive the three-parton-to-three-parton $k_T$-dependent hard kernel at leading order of the coupling constant, and find that it leads to about 5% correction to the pion electromagnetic form factor in the whole range of experimentally accessible momentum transfer squared. This subleading contribution is much smaller than the leading-order twist-2, next-to-leading-order twist-2 and leading-order two-parton twist-3 ones, which have been calculated in the literature.

14 pages, 10 figures, version to appear in PRD

References in corpus (8)

• Charged pion form factor between Q^2=0.60 and 2.45 GeV^2. II. Determination of, and results for, the pion form factor
• Twist-3 Formalism for Single Transverse Spin Asymmetry Reexamined: Semi-Inclusive Deep Inelastic Scattering
• Pion transition form factor in k_T factorization
• Next-to-leading-order correction to pion form factor in $k_T$ factorization
• Next-to-leading-order corrections to exclusive processes in $k_T$ factorization
• Testing for kt-factorization with inclusive prompt photon production at LHC
• Gauge Invariance and k_T-Factorization of Exclusive Processes
• Three-Parton Contributions to B --> M_1 M_2 Annihilation at Leading Order

Cited by in corpus (13)

• Meson Transition Form Factors in Light-Front Holographic QCD
• Subleading power corrections to the pion-photon transition form factor in QCD
• The NLO twist-3 contribution to the pion electromagnetic form factors in $k_T$ factorization
• Time-like pion electromagnetic form factors in $k_T$ factorization with the Next-to-leading-order twist-3 contribution
• The PQCD approach towards to next-to-leading order: a short review
• Three-parton contribution to the $B\to \pi$ form factors in $k_T$ factorization
• The $\rho {\gamma }^{\ast }\to \pi (\rho )$ transition form factors in the Perturbative QCD factorization approach
• Pion and Kaon form factors in the perturbative QCD approach
• Rho-pion transition form factors in the $k_T$ factorization formulism revisited
• Determination of pion distribution amplitudes from the electromagnetic form factor with the data-driven dispersion relation
• Revisiting the factorization theorem for $\rho {\gamma }^{\ast }\to \pi (\rho )$ at twist 3
• Twist-3 contributions to $\gamma \gamma \to {\pi }^{+}{\pi }^{-},K^{+}{K}^{-}$ processes in perturbative QCD approach
• A Note on the $k_T$-Factorization for Exclusive Processes