Origin of SU(2)-flavor-symmetry breaking in antiquark distributions

Journal Article · Thu Aug 01 04:00:00 EDT 1991 · Physical Review, D (Particles Fields); (United States)

DOI:https://doi.org/10.1103/PhysRevD.44.717· OSTI ID:5309285

Kumano, S; Londergan, J T ^[1]

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1. Department of Physics and Nuclear Theory Center, Indiana University, 2401 Milo B. Sampson Lane, Bloomington, IN (USA)

The New Muon Collaboration has recently measured the electromagnetic structure functions {ital F}{sub 2} through deep-inelastic muon scattering from protons and deuterons. Structure functions ({ital F}{sub 2}{sup {ital e}{ital p}}({ital x}){minus}{ital F}{sub 2}{sup {ital e}{ital n}}({ital x})) have been measured to very small Bjorken {ital x}. The results seem to violate the Gottfried sum rule. We discuss various possible reasons for this result, including significant contributions from valence quarks at very small {ital x} and SU(2)-flavor breaking in the sea. We show that the pionic contribution to the sea-quark distributions gives qualitative agreement with estimates of the SU(2)-flavor-breaking contribution. We discuss various experiments which could give a direct measurement of {ital {bar u}}-{ital {bar d}}. We make qualitative estimates of shadowing effects in the deuteron and their impact on the extracted neutron structure functions.

• DOE Contract Number: FG02-87ER40365
• OSTI ID: 5309285
• Journal Information: Physical Review, D (Particles Fields); (United States), Journal Name: Physical Review, D (Particles Fields); (United States) Vol. 44:3; ISSN PRVDA; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

645203* -- High Energy Physics-- Particle Interactions & Properties-Theoretical-- Weak Interactions & Properties
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
COMPOSITE MODELS
DEEP INELASTIC SCATTERING
DRELL MODEL
ELEMENTARY PARTICLES
EQUATIONS
FERMIONS
FLAVOR MODEL
FUNCTIONS
INELASTIC SCATTERING
INTERACTIONS
ISOSPIN
LEPTON-BARYON INTERACTIONS
LEPTON-HADRON INTERACTIONS
LEPTON-NUCLEON INTERACTIONS
LIE GROUPS
MATHEMATICAL MODELS
MOMENTUM TRANSFER
MUON-DEUTERON INTERACTIONS
MUON-NUCLEON INTERACTIONS
MUON-PROTON INTERACTIONS
PARTICLE INTERACTIONS
PARTICLE MODELS
PARTICLE PROPERTIES
PARTONS
PAULI PRINCIPLE
POSTULATED PARTICLES
QUARK MODEL
QUARK-ANTIQUARK INTERACTIONS
QUARKS
RENORMALIZATION
SCATTERING
STRUCTURE FUNCTIONS
SU GROUPS
SU-2 GROUPS
SUM RULES
SYMMETRY GROUPS