Quenched chiral logarithms

Technical Report · Wed Apr 01 04:00:00 EST 1992

OSTI ID:6803295

Sharpe, S R ^[1]

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1. Continuous Electron Beam Accelerator Facility, Newport News, VA (United States)

I develop a diagrammatic method for calculating chiral logarithms in the quenched approximation. While not rigorous, the method is based on physically reasonable assumptions, which can be tested by numerical simulations. The main results are that, at leading order in the chiral expansion, (a) there are no chiral logarithms in quenched f[sub [pi]] m[sub u] = m[sub d]; (b) the chiral logarithms in B[sub K] and related kaon B-parameters are, for m[sub d] = m[sub s] the same in the quenched approximation as in the full theory (c) for m[sub [pi]] and the condensate, there are extra chiral logarithms due to loops containing the [eta][prime], which lead to a peculiar non-analytic dependence of these quantities on the bare quark mass. Following the work of Gasser and Leutwyler, I discuss how there is a predictable finite volume dependence associated with each chiral logarithm. I compare the resulting predictions with numerical results: for most quantities the expected volume dependence is smaller than the errors. but for B[sub V] and B[sub A] there is an observed dependence which is consistent with the predictions.

• Research Organization: Washington Univ., Seattle, WA (United States). Dept. of Physics
• Sponsoring Organization: DOE; USDOE, Washington, DC (United States)
• DOE Contract Number: FG06-91ER40614; AC05-84ER40150
• OSTI ID: 6803295
• Report Number(s): DOE/ER/40614-25; ON: DE93010195
• Country of Publication: United States
• Language: English

Related Subjects

665400* -- Quantum Physics Aspects of Condensed Matter-- (1992-)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
99 GENERAL AND MISCELLANEOUS
990200 -- Mathematics & Computers
ALGORITHMS
BOSONS
CHIRAL SYMMETRY
COMPOSITE MODELS
ELEMENTARY PARTICLES
FIELD THEORIES
HADRONS
LIE GROUPS
MATHEMATICAL LOGIC
MATHEMATICAL MODELS
MATRIX ELEMENTS
MESONS
PARTICLE MODELS
PIONS
PSEUDOSCALAR MESONS
QUANTUM CHROMODYNAMICS
QUANTUM FIELD THEORY
QUARK MODEL
SU GROUPS
SU-2 GROUPS
SYMMETRY
SYMMETRY GROUPS
WARD IDENTITY