Octet baryon masses and sigma terms from an SU(3) chiral extrapolation

Journal Article · Fri Jan 01 04:00:00 EST 2010 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.81.014503· OSTI ID:21408984

Young, R D ^[1]; Thomas, A W ^[2]

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1. Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States)
2. Jefferson Lab, 12000 Jefferson Avenue, Newport News, Virginia 23606 (United States)

We report an analysis of the impressive new lattice simulation results for octet baryon masses in 2+1-flavor QCD. The analysis is based on a low-order expansion about the chiral SU(3) limit in which the symmetry breaking arises from terms linear in the quark masses plus the variation of the Goldstone boson masses in the leading chiral loops. The baryon masses evaluated at the physical light-quark masses are in remarkable agreement with the experimental values, with a model dependence considerably smaller than the rather small statistical uncertainty. From the mass formulas one can evaluate the sigma commutators for all octet baryons. This yields an accurate value for the pion-nucleon sigma commutator. It also yields the first determination of the strangeness sigma term based on 2+1-flavor lattice QCD and, in general, the sigma commutators provide a resolution to the difficult issue of fine-tuning the strange-quark mass.

• OSTI ID: 21408984
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 1 Vol. 81; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BARYONS
BOSONS
CHIRALITY
COMMUTATORS
COMPOSITE MODELS
COMPUTERIZED SIMULATION
CONSTRUCTIVE FIELD THEORY
CURRENT COMMUTATORS
D QUARKS
ELEMENTARY PARTICLES
EXPANSION
EXTRAPOLATION
FERMIONS
FIELD THEORIES
FLAVOR MODEL
GOLDSTONE BOSONS
HADRONS
LATTICE FIELD THEORY
LIE GROUPS
MASS
MASS FORMULAE
MATHEMATICAL MODELS
MATHEMATICAL OPERATORS
MATHEMATICAL SOLUTIONS
MESONS
NUCLEONS
NUMERICAL SOLUTION
PARTICLE MODELS
PARTICLE PROPERTIES
PIONS
POSTULATED PARTICLES
PSEUDOSCALAR MESONS
QUANTUM CHROMODYNAMICS
QUANTUM FIELD THEORY
QUANTUM OPERATORS
QUARK MODEL
QUARKS
RESOLUTION
S QUARKS
SIGMA TERMS
SIMULATION
STRANGE PARTICLES
STRANGENESS
SU GROUPS
SU-3 GROUPS
SYMMETRY BREAKING
SYMMETRY GROUPS
U QUARKS