Effects of staggered fermions and mixed actions on the scalar correlator
Abstract
We provide the analytic predictions for the flavor nonsinglet scalar correlator, which will enable determination of the scalar meson mass from the lattice scalar correlator. We consider simulations with 2+1 staggered sea quarks and staggered or chiral valence quarks. At small u/d masses the correlator is dominated by the bubble contribution, which is the intermediate state with two pseudoscalar mesons. We determine the bubble contribution within staggered and mixed chiral perturbation theory. Its effective mass is smaller than the mass of {pi}{eta}, which is the lightest intermediate state in proper 2+1 QCD. The unphysical effective mass is a consequence of the taste breaking that makes possible the intermediate state with mass 2M{sub {pi}}. We find that the scalar correlator can be negative in the simulations with mixed quark actions if the sea and valencequark masses are tuned by matching the pion masses M{sub val,val}=M{sub {pi}{sub 5}}.
 Authors:
 Department of Physics, University of Ljubljana, Jadranska 19, 1000 Ljubljana (Slovenia) and Institute Jozef Stefan, Jamova 39, 1000 Ljubljana (Slovenia)
 Publication Date:
 OSTI Identifier:
 20774618
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. D, Particles Fields; Journal Volume: 73; Journal Issue: 1; Other Information: DOI: 10.1103/PhysRevD.73.014506; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ACTION INTEGRAL; CHIRAL SYMMETRY; CHIRALITY; COMPUTERIZED SIMULATION; EFFECTIVE MASS; FLAVOR MODEL; INTERMEDIATE STATE; LATTICE FIELD THEORY; PERTURBATION THEORY; PIONS; QUANTUM CHROMODYNAMICS; QUARKS; SCALAR MESONS; SCALARS; VALENCE
Citation Formats
Prelovsek, S. Effects of staggered fermions and mixed actions on the scalar correlator. United States: N. p., 2006.
Web. doi:10.1103/PhysRevD.73.014506.
Prelovsek, S. Effects of staggered fermions and mixed actions on the scalar correlator. United States. doi:10.1103/PhysRevD.73.014506.
Prelovsek, S. Sun .
"Effects of staggered fermions and mixed actions on the scalar correlator". United States.
doi:10.1103/PhysRevD.73.014506.
@article{osti_20774618,
title = {Effects of staggered fermions and mixed actions on the scalar correlator},
author = {Prelovsek, S.},
abstractNote = {We provide the analytic predictions for the flavor nonsinglet scalar correlator, which will enable determination of the scalar meson mass from the lattice scalar correlator. We consider simulations with 2+1 staggered sea quarks and staggered or chiral valence quarks. At small u/d masses the correlator is dominated by the bubble contribution, which is the intermediate state with two pseudoscalar mesons. We determine the bubble contribution within staggered and mixed chiral perturbation theory. Its effective mass is smaller than the mass of {pi}{eta}, which is the lightest intermediate state in proper 2+1 QCD. The unphysical effective mass is a consequence of the taste breaking that makes possible the intermediate state with mass 2M{sub {pi}}. We find that the scalar correlator can be negative in the simulations with mixed quark actions if the sea and valencequark masses are tuned by matching the pion masses M{sub val,val}=M{sub {pi}{sub 5}}.},
doi = {10.1103/PhysRevD.73.014506},
journal = {Physical Review. D, Particles Fields},
number = 1,
volume = 73,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}

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