Anatomy of relativistic pion loop corrections to the electromagnetic nucleon coupling

Abstract

We present a relativistic formulation of pion loop corrections to the coupling of photons with nucleons on the light-front. Vertex and wave function renormalization constants are computed to lowest order in the pion field, including their nonanalytic behavior in the chiral limit, and studied numerically as a function of the ultraviolet cutoff. Particular care is taken to explicitly verify gauge invariance and Ward-Takahashi identity constraints to all orders in the m_pi expansion. The results are used to compute the chiral corrections to matrix elements of local operators, related to moments of deep-inelastic structure functions. Finally, comparisons of results for pseudovector and pseudoscalar coupling allows the resolution of a long-standing puzzle in the computation of pion cloud corrections to structure function moments.

37 pages, 7 figures, 1 table; final version published in Phys. Rev. D

References in corpus (6)

• Pion momentum distributions in the nucleon in chiral effective theory
• <x>_{u-d} from lattice QCD at nearly physical quark masses
• Broken Chiral Symmetry on a Null Plane
• On chiral corrections to nucleon GPD
• Comment on "Taming the pion cloud of the nucleon"
• Manifestly-covariant chiral PT calculation of nucleon Compton scattering

Cited by in corpus (19)

• First Monte Carlo global QCD analysis of pion parton distributions
• Pion structure function from leading neutron electroproduction and SU(2) flavor asymmetry
• $\bar{d}-\bar{u}$ asymmetry in the proton in chiral effective theory
• Chiral dynamics and peripheral transverse densities
• Towards the three-dimensional parton structure of the pion: Integrating transverse momentum data into global QCD analysis
• Strange quark asymmetry in the proton in chiral effective theory
• Parton distributions from nonlocal chiral SU(3) effective theory. I. Splitting functions
• Chiral Light Front Perturbation Theory and the Flavor Dependence of the Light-Quark Nucleon Sea
• Constraints on $s-\bar{s}$ asymmetry of the proton in chiral effective theory
• Parton distributions from nonlocal chiral SU(3) effective theory: Flavor asymmetries
• Light-front representation of chiral dynamics with Delta isobar and large-N_c relations
• An Improved Hadronic Model for Pion Electroproduction
• Model Dependence of the Pion Form Factor Extracted from Pion Electro-production
• Quantum-mechanical picture of peripheral chiral dynamics
• Pions in Proton Structure and Everywhere Else
• Octet and decuplet baryon self-energies in relativistic SU(3) chiral effective theory
• Flavor asymmetry from the non-perturbative nucleon sea
• Flavor symmetry breaking in the $\Delta$ sea
• Nucleon parton distributions from hadronic quantum fluctuations