Isospin violation in QCD sum rules for baryons

Journal Article · Wed Sep 01 04:00:00 EDT 1993 · Physical Review, D (Particles Fields); (United States)

DOI:https://doi.org/10.1103/PhysRevD.48.2304· OSTI ID:6217192

Adami, C ^[1]; Drukarev, E G ^[2]; Ioffe, B L ^[3]

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1. W. K. Kellogg Radiation Laboratory, California Institute of Technology, Pasadena, California 91125 (United States)
2. St. Petersburg Nuclear Physics Institute, Gatchina, 188 350 St. Petersburg (Russian Federation)
3. Institute of Theoretical and Experimental Physics, B. Cheremushkinskaya 25, 117 259 Moscow (Russian Federation)

We thoroughly analyze isospin-violating effects in QCD sum rules for the masses of nucleons, [Sigma], and [Xi] hyperons. After comparing with experimental mass splittings in isotopic multiplets, we obtain for the isospin breaking in the quark condensate [l angle]0[vert bar][ital [bar u]u][minus][ital [bar d]d][vert bar]0[r angle]/[l angle]0[vert bar][ital [bar u]u][vert bar]0[r angle]=(2[plus minus]1)[times]10[sup [minus]3], a value significantly smaller than the one usually adopted. We present arguments in favor of our result and critically analyze previous estimates. The value of the quark mass difference [ital m][sub [ital d]][minus][ital m][sub [ital u]]=3.0[plus minus]1.0 MeV (at normalization point [bar [mu]]=0.5 GeV) is also determined.

• OSTI ID: 6217192
• Journal Information: Physical Review, D (Particles Fields); (United States), Journal Name: Physical Review, D (Particles Fields); (United States) Vol. 48:5; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

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72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BARYONS
CHIRALITY
ELEMENTARY PARTICLES
EQUATIONS
FERMIONS
FIELD THEORIES
HADRONS
HYPERONS
ISOSPIN
MASS DIFFERENCE
NUCLEONS
OPERATOR PRODUCT EXPANSION
PARTICLE PROPERTIES
QUANTUM CHROMODYNAMICS
QUANTUM FIELD THEORY
QUARK CONDENSATION
SERIES EXPANSION
SIGMA BARYONS
STRANGE PARTICLES
SUM RULES
SYMMETRY BREAKING