The Validity of Charge Symmetry for Parton Distributions

Abstract

Recent measurements of the Gottfried sum rule have focused attention on the possibility of substantial flavor symmetry breaking in the proton sea. This is confirmed by pp and pD Drell-Yan processes measured at FNAL. Theoretical models used to `prove' flavor symmetry breaking rely on the assumption of charge symmetric parton distributions. Substantial charge symmetry violation [CSV] could affect current tests of flavor symmetry. In this review we examine the possibility of CSV for parton distributions. We first give definitions for structure functions without making the usual assumption of charge symmetry. Next we make estimates of CSV for both valence and sea quark distributions. We list a set of relations which must hold if charge symmetry is valid, and review current experimental limits on CSV. We propose a series of experimental tests of charge symmetry. These tests could either detect CSV, or they could provide stronger upper limits on CSV effects. We discuss CSV contributions to sum rules, and we propose sum rules which could differentiate between flavor symmetry, and charge symmetry violation in nuclear systems.

74 pages, including 26 figures

Cited by in corpus (44)

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• Flavor Asymmetry of Light Quarks in the Nucleon Sea
• The Spin Structure of the Nucleon
• The Asymmetry of Antimatter in the Proton
• Novel Phenomenology of Parton Distributions from the Drell-Yan Process
• High-Energy Hadron-Induced Dilepton Production from Nucleons and Nuclei
• A lattice determination of moments of unpolarised nucleon structure functions using improved Wilson fermions
• Parton distribution functions in the pion from lattice QCD
• Charge Symmetry at the Partonic Level
• Virtual meson cloud of the nucleon and generalized parton distributions
• Structure functions for the three nucleon system
• Parton Distributions for the Octet and Decuplet Baryons
• Nucleon sea in the effective chiral quark model
• Finite-Q^2 corrections to parity-violating DIS
• Contribution of asymmetric strange-antistrange sea to the Paschos-Wolfenstein relation
• Model for Polarized and Unpolarized Parton Density Functions in the Nucleon
• Charge Symmetry Breaking Effects in Pion and Kaon Structure
• The neutron negative central charge density: an inclusive-exclusive connection
• A New Analysis of Charge Symmetry Violation in Parton Distributions
• Nonperturbative versus perturbative effects in generalized parton distributions
• NNLO nucleon parton distributions from a light-cone quark model dressed with its virtual meson cloud
• Charge Symmetry Breaking in Parton Distribution Functions from Lattice QCD
• Spin Dependent Parton Distributions in a Bound Nucleon
• Collinear parton distributions and the structure of the nucleon sea in a light-front meson-cloud model
• Charge symmetry breaking from a chiral extrapolation of moments of quark distribution functions
• Testing Partonic Charge Symmetry at a High-Energy Electron Collider
• Charge Symmetry Breaking in Spin Dependent Parton Distributions and the Bjorken Sum Rule
• Physics of the Nucleon Sea Quark Distributions
• Deep inelastic scattering on asymmetric nuclei
• Pion-Exchange and Fermi-Motion Effects on the Proton-Deuteron Drell-Yan Process
• Additional Corrections to the Gross-Llewellyn Smith Sum Rule
• Experimental Tests of Charge Symmetry Violation in Parton Distributions
• Flavor Asymmetry of the Nucleon Sea and W Boson Production
• Possible Explanations for the NuTeV Weinberg Angle Measurement
• Nuclear Effects in Deep Inelastic Scattering of Charged-Current Neutrino off Nuclear
• Effect due to charge symmetry violation on the Paschos-Wolfenstein relation
• Electromagnetic contribution to charge symmetry violation in parton distributions
• Parton Charge Symmetry Violation: Electromagnetic Effects and W Production Asymmetries
• Flavor asymmetry from the non-perturbative nucleon sea
• A Vision of Hadronic Physics
• The spin structure function of the neutron
• The Inclusive-Exclusive Connection and the Neutron Negative Central Charge Density
• Progress in resolving charge symmetry violation in nucleon structure
• Nucleon Resonances and Quark Structure