Evidence for hard chiral logarithms in quenched lattice QCD

Journal Article · Fri Sep 01 04:00:00 EDT 1995 · Physical Review, D

DOI:https://doi.org/10.1103/PhysRevD.52.R2614· OSTI ID:115919

Kim, S; Sinclair, D K ^[1]

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1. HEP Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439 (United States)

We present the first direct evidence that quenched QCD differs from full QCD in the chiral ({ital m}{sub {ital q}}{r_arrow}0) limit, as predicted by chiral perturbation theory, from our quenched lattice QCD simulations at {beta}=6/{ital g}{sup 2}=6.0. We measure the spectrum of light hadrons on 16{sup 3}{times}64, 24{sup 3}{times}64, and 32{sup 3}{times}64 lattices, using staggered quarks of masses {ital m}{sub {ital q}}=0.01, {ital m}{sub {ital q}}=0.005, and {ital m}{sub {ital q}}=0.0025. The pion masses show evidence for logarithmic violations of the PCAC relation {ital m}{sub {pi}}{sup 2}{proportional_to}{ital m}{sub {ital q}}, as predicted by quenched chiral perturbation theory. The dependence on spatial lattice volume precludes this being a finite size effect. No evidence is seen for such chiral logarithms in the behavior of the chiral condensate {l_angle}{bar {psi}}{psi}{r_angle}.

• Research Organization: Argonne National Laboratory (ANL), Argonne, IL
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 115919
• Journal Information: Physical Review, D, Journal Name: Physical Review, D Journal Issue: 5 Vol. 52; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
CHIRAL SYMMETRY
CONDENSATES
LATTICE FIELD THEORY
MASS
PCAC THEORY
PERTURBATION THEORY
QUANTUM CHROMODYNAMICS
QUARKS
QUENCHING
SIMULATION
SPECTRA
VIOLATIONS