Abstract

We discuss the pion and kaon distribution amplitudes up to twist-3 in the context of the random instanton vacuum (RIV). We construct explicitly the pertinent quasipion and quasikaon distributions in the RIV, and analyze them in leading order in the diluteness factor, at a resolution fixed by the inverse instanton size. The distribution amplitudes (DA) follow from the large momentum limit. The results at higher resolution are discussed using QCD evolution, and compared to their asymptotic limits and some lattice results.

Highlights

  • Light cone distributions are central to the description of hard inclusive and exclusive processes

  • Ji [1] has put forth the concept of spacelike quasiparton distributions that are perturbatively matched to the timelike light cone distributions [2–7]

  • In the random instanton vacuum (RIV) the pion quasi-distribution amplitudes (DA) is a state made of zeromodes and nonzero-modes that interact collectively

Read more

Summary

INTRODUCTION

Light cone distributions are central to the description of hard inclusive and exclusive processes. The parton distribution functions are defined on the light front, and their moments usually fitted using large empirical data banks They are not readily amenable to a nonperturbative and first principle formulation using lattice simulations. The quasiparton distribution matrix elements calculated in a fixed size Euclidean lattice QCD, have been argued to match those obtained through LSZ reduction in continuum Minkowski QCD, to all orders in perturbation theory [9] Some variants of this formulation can be found in the form of pseudodistributions [10], and lattice cross sections [11]. We will analyze the twoparticle pion and kaon quasidistributions up to twist-3 in the RIV, and extract the light cone distribution amplitudes in the large momentum limit.

INSTANTON EFFECTS
TWIST AND CHIRAL STRUCTURES OF THE DA OF THE PION
Pseudoscalar, Γ = γ5
Axial-vector, twist-2, Γ = γzγ5
QCD EVOLUTION
CONCLUSIONS

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.