Aspects and consequences of a dressed-quark-gluon vertex

Journal Article · Wed Sep 01 00:00:00 EDT 2004 · Physical Review. C, Nuclear Physics

DOI:https://doi.org/10.1103/PhysRevC.70.035205· OSTI ID:20695543

Bhagwat, M S ^[1]; Hoell, A; Krassnigg, A ^[2]; Roberts, C D ^[2]; Tandy, P C

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1. Center for Nuclear Research, Department of Physics, Kent State University, Kent, Ohio 44242 (United States)
2. Physics Division, Argonne National Laboratory, Argonne, Illinois 60439-4843 (United States)

Features of the dressed-quark-gluon vertex and their role in the gap and Bethe-Salpeter equations are explored. It is argued that quenched lattice data indicate the existence of net attraction in the color-octet projection of the quark-antiquark scattering kernel. The study employs a vertex model whose diagrammatic content is explicitly enumerable. That enables the systematic construction of a vertex-consistent Bethe-Salpeter kernel and thereby an exploration of the consequences for the strong interaction spectrum of attraction in the color-octet channel. With rising current-quark mass the rainbow-ladder truncation is shown to provide an increasingly accurate estimate of a bound state's mass. Moreover, the calculated splitting between vector and pseudoscalar meson masses vanishes as the current-quark mass increases, which argues for the mass of the pseudoscalar partner of the {upsilon}(1S) to be above 9.4 GeV. With the amount of attraction suggested by lattice data color-antitriplet diquarks are absent from the strong interaction spectrum.

• OSTI ID: 20695543
• Journal Information: Physical Review. C, Nuclear Physics, Vol. 70, Issue 3; Other Information: DOI: 10.1103/PhysRevC.70.035205; (c) 2004 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2813
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BETHE-SALPETER EQUATION
BOUND STATE
CHIRAL SYMMETRY
GEV RANGE
GLUONS
LATTICE FIELD THEORY
MASS FORMULAE
PSEUDOSCALAR MESONS
QUANTUM CHROMODYNAMICS
QUARK-ANTIQUARK INTERACTIONS
QUARKS
REST MASS
STRONG INTERACTIONS
SYMMETRY BREAKING
UPSILON-9460 MESONS
VERTEX FUNCTIONS