2007/07/16 by C. Bérnard, Claude Bernard, Carleton DeTar +3 · 1 citation
Physics and Astronomy · #Particle physics theoretical and experimental studies #Physics of Superconductivity and Magnetism #Quantum Chromodynamics and Particle Interactions #hep-lat
paper · pdf · doi:10.1103/physrevd.76.094504
published as Phys.Rev.D76:094504,2007 · 23 pp., 3 figs., submitted to Phys. Rev. D
arxiv created 2007/07/16 · openalex publication_date 2007/11/07 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
With sufficiently light up and down quarks the isovector (a0) and isosinglet (f0) scalar meson propagators are dominated at large distance by two-meson states. In the staggered-fermion formulation of lattice quantum chromodynamics, taste-symmetry breaking causes a proliferation of two-meson states that further complicates the analysis of these channels. Many of them are unphysical artifacts of the lattice approximation. They are expected to disappear in the continuum limit. The staggered-fermion fourth-root procedure has its purported counterpart in rooted staggered chiral perturbation theory (rS\ensuremathχPT). Fortunately, the rooted theory provides a strict framework that permits the analysis of scalar meson correlators in terms of only a small number of low-energy couplings. Thus the analysis of the point-to-point scalar meson correlators in this context gives a useful consistency check of the fourth-root procedure and its proposed chiral realization. Through numerical simulation we have measured correlators for both the a0 and f0 channels in the ``Asqtad'' improved staggered-fermion formulation in a lattice ensemble with lattice spacing a=0.12 fm. We analyze those correlators in the context of rS\ensuremathχPT and obtain values of the low-energy chiral couplings that are reasonably consistent with previous determinations.