Comparison of Chiral Perturbation Theory and QCD Sum Rule Results for Pseudoscalar Isoscalar-Isovector Mixing

Abstract

The forms of the neutral, non-strange pseudoscalar propagator matrix and mixed axial current correlator, $\lngle0|T(A_μ^3 A_ν^8)|0\rangle$, are discussed at next-to-leading (one-loop) order in chiral perturbation theory, and the results compared to those obtained using QCD sum rules. This comparison provides a check of the truncations employed in the sum rule treatment of the current correlator. Values for the slope of the correlator with $q^2$ in the two approaches are found to differ by more than an order of magnitude and the source of this discrepancy is shown to be the incorrect chiral behavior of the sum rule result.

14 pages, uses REVTEX Entire manuscript available as a ps file at http://www.physics.adelaide.edu.au/theory/home.html . Also available via anonymous ftp at ftp://adelphi.adelaide.edu.au/pub/theory/ADP-95-2.T169.ps To appear in Physics Letters B

References in corpus (4)

• Chiral perturbation theory
• Constraints on the momentum dependence of rho-omega mixing
• Charge symmetry breaking via rho-omega mixing from model quark-gluon dynamics
• QCD sum rules vs. chiral perturbation theory

Cited by in corpus (10)

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• Analysis of rho-omega interference in the pion form-factor
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• Strong Isospin-Breaking Effects in K-->pi pi at Next-to-Leading Order in the Chiral Expansion
• The Mixed-Isospin Vector Current Correlator in Chiral Perturbation Theory and QCD Sum Rules
• Two Model-Independent Results for the Momentum Dependence of Rho-Omega Mixing
• The Strong Isospin-Breaking Correction for the Gluonic Penguin Contribution to epsilon'/epsilon at Next-to-Leading Order in the Chiral Expansion
• Isospin Breaking Effects in the Extraction of Isoscalar and Isovector Spectral Functions From $e^{+}{e}^{-}\to hadrons$
• Vector Meson Mixing and Charge Symmetry Violation
• QCD Sum Rules for the Isospin-Breaking Axial Correlator with Correct Chiral Behavior