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Title: First results from 2+1-flavor domain wall QCD: Mass spectrum, topology change, and chiral symmetry with L{sub s}=8

Abstract

We present results for the static interquark potential, light meson and baryon masses, and light pseudoscalar meson decay constants obtained from simulations of domain wall QCD with one dynamical flavour approximating the s quark, and two degenerate dynamical flavours with input bare masses ranging from m{sub s} to m{sub s}/4 approximating the u and d quarks. We compare these quantities obtained using the Iwasaki and DBW2 improved gauge actions, and actions with larger rectangle coefficients, on 16{sup 3}x32 lattices. We seek parameter values at which both the chiral symmetry breaking residual mass due to the finite lattice extent in the fifth dimension and the Monte Carlo time history for topological charge are acceptable for this set of quark masses at lattice spacings above 0.1 fm. We find that the Iwasaki gauge action is best, demonstrating the feasibility of using QCDOC to generate ensembles which are good representations of the QCD path integral on lattices of up to 3 fm in spatial extent with lattice spacings in the range 0.09-0.13 fm. Despite large residual masses and a limited number of sea quark-mass values with which to perform chiral extrapolations, our results for light hadronic physics scale and agree with experimental measurementsmore » within our statistical uncertainties.« less

Authors:
; ; ; ; ; ;  [1];  [2];  [3]; ; ; ; ;  [4];  [5];  [2];  [2];  [6];  [6];  [2] more »;  [6];  [7]; ;  [8] « less
  1. SUPA, School of Physics, The University of Edinburgh, Edinburgh EH9 3JZ (United Kingdom)
  2. RIKEN-BNL Research Center, Brookhaven National Laboratory, Upton, New York 11973 (United States)
  3. (United States)
  4. Physics Department, Columbia University, New York, New York 10027 (United States)
  5. Center for Computational Science, 3 Cummington Street, Boston University, Massachusetts 02215 (United States)
  6. (Japan)
  7. Jefferson Laboratory, Newport News, Virginia 23606 (United States)
  8. Brookhaven National Laboratory, Upton, New York 11973 (United States) (and others)
Publication Date:
OSTI Identifier:
20929558
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 11; Other Information: DOI: 10.1103/PhysRevD.75.114501; (c) 2007 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; BARYONS; CHIRAL SYMMETRY; CHIRALITY; D QUARKS; EXTRAPOLATION; FLAVOR MODEL; MASS; MASS SPECTRA; MONTE CARLO METHOD; PARTICLE DECAY; PATH INTEGRALS; PSEUDOSCALAR MESONS; QUANTUM CHROMODYNAMICS; S QUARKS; SIMULATION; SYMMETRY BREAKING; TOPOLOGY

Citation Formats

Antonio, D. J., Bowler, K. C., Boyle, P. A., Hart, A., Kennedy, A. D., Kenway, R. D., Tweedie, R. J., Blum, T., Physics Department, University of Connecticut, Storrs Connecticut, 06269-3046, Christ, N. H., Cohen, S. D., Li, S., Lin, M. F., Mawhinney, R. D., Clark, M. A., Dawson, C., Hashimoto, K., Radiation Laboratory, RIKEN, Wako, Saitama 351-0198, Institute for Theoretical Physics, Kanazawa University, Kakuma, Kanazawa, 920-1192, Izubuchi, T., Institute for Theoretical Physics, Kanazawa University, Kakuma, Kanazawa, 920-1192, Joo, B., Jung, C., and Soni, A.. First results from 2+1-flavor domain wall QCD: Mass spectrum, topology change, and chiral symmetry with L{sub s}=8. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.114501.
Antonio, D. J., Bowler, K. C., Boyle, P. A., Hart, A., Kennedy, A. D., Kenway, R. D., Tweedie, R. J., Blum, T., Physics Department, University of Connecticut, Storrs Connecticut, 06269-3046, Christ, N. H., Cohen, S. D., Li, S., Lin, M. F., Mawhinney, R. D., Clark, M. A., Dawson, C., Hashimoto, K., Radiation Laboratory, RIKEN, Wako, Saitama 351-0198, Institute for Theoretical Physics, Kanazawa University, Kakuma, Kanazawa, 920-1192, Izubuchi, T., Institute for Theoretical Physics, Kanazawa University, Kakuma, Kanazawa, 920-1192, Joo, B., Jung, C., & Soni, A.. First results from 2+1-flavor domain wall QCD: Mass spectrum, topology change, and chiral symmetry with L{sub s}=8. United States. doi:10.1103/PHYSREVD.75.114501.
Antonio, D. J., Bowler, K. C., Boyle, P. A., Hart, A., Kennedy, A. D., Kenway, R. D., Tweedie, R. J., Blum, T., Physics Department, University of Connecticut, Storrs Connecticut, 06269-3046, Christ, N. H., Cohen, S. D., Li, S., Lin, M. F., Mawhinney, R. D., Clark, M. A., Dawson, C., Hashimoto, K., Radiation Laboratory, RIKEN, Wako, Saitama 351-0198, Institute for Theoretical Physics, Kanazawa University, Kakuma, Kanazawa, 920-1192, Izubuchi, T., Institute for Theoretical Physics, Kanazawa University, Kakuma, Kanazawa, 920-1192, Joo, B., Jung, C., and Soni, A.. Fri . "First results from 2+1-flavor domain wall QCD: Mass spectrum, topology change, and chiral symmetry with L{sub s}=8". United States. doi:10.1103/PHYSREVD.75.114501.
@article{osti_20929558,
title = {First results from 2+1-flavor domain wall QCD: Mass spectrum, topology change, and chiral symmetry with L{sub s}=8},
author = {Antonio, D. J. and Bowler, K. C. and Boyle, P. A. and Hart, A. and Kennedy, A. D. and Kenway, R. D. and Tweedie, R. J. and Blum, T. and Physics Department, University of Connecticut, Storrs Connecticut, 06269-3046 and Christ, N. H. and Cohen, S. D. and Li, S. and Lin, M. F. and Mawhinney, R. D. and Clark, M. A. and Dawson, C. and Hashimoto, K. and Radiation Laboratory, RIKEN, Wako, Saitama 351-0198 and Institute for Theoretical Physics, Kanazawa University, Kakuma, Kanazawa, 920-1192 and Izubuchi, T. and Institute for Theoretical Physics, Kanazawa University, Kakuma, Kanazawa, 920-1192 and Joo, B. and Jung, C. and Soni, A.},
abstractNote = {We present results for the static interquark potential, light meson and baryon masses, and light pseudoscalar meson decay constants obtained from simulations of domain wall QCD with one dynamical flavour approximating the s quark, and two degenerate dynamical flavours with input bare masses ranging from m{sub s} to m{sub s}/4 approximating the u and d quarks. We compare these quantities obtained using the Iwasaki and DBW2 improved gauge actions, and actions with larger rectangle coefficients, on 16{sup 3}x32 lattices. We seek parameter values at which both the chiral symmetry breaking residual mass due to the finite lattice extent in the fifth dimension and the Monte Carlo time history for topological charge are acceptable for this set of quark masses at lattice spacings above 0.1 fm. We find that the Iwasaki gauge action is best, demonstrating the feasibility of using QCDOC to generate ensembles which are good representations of the QCD path integral on lattices of up to 3 fm in spatial extent with lattice spacings in the range 0.09-0.13 fm. Despite large residual masses and a limited number of sea quark-mass values with which to perform chiral extrapolations, our results for light hadronic physics scale and agree with experimental measurements within our statistical uncertainties.},
doi = {10.1103/PHYSREVD.75.114501},
journal = {Physical Review. D, Particles Fields},
number = 11,
volume = 75,
place = {United States},
year = {Fri Jun 01 00:00:00 EDT 2007},
month = {Fri Jun 01 00:00:00 EDT 2007}
}
  • We present results for the static interquark potential, light meson and baryon masses, and light pseudoscalar meson decay constants obtained from simulations of domain wall QCD with one dynamical flavour approximating themore » $s$ quark, and two degenerate dynamical flavours with input bare masses ranging from $$m_s$$ to $$m_s/4$$ approximating the $u$ and $d$ quarks. We compare these quantities obtained using the Iwasaki and DBW2 improved gauge actions, and actions with larger rectangle coefficients, on $$16^3\times32$$ lattices. We seek parameter values at which both the chiral symmetry breaking residual mass due to the finite lattice extent in the fifth dimension and the Monte Carlo time history for topological charge are acceptable for this set of quark masses at lattice spacings above 0.1 fm. We find that the Iwasaki gauge action is best, demonstrating the feasibility of using QCDOC to generate ensembles which are good representations of the QCD path integral on lattices of up to 3 fm in spatial extent with lattice spacings in the range 0.09-0.13 fm. Despite large residual masses and a limited number of sea quark mass values with which to perform chiral extrapolations, our results for light hadronic physics scale and agree with experimental measurements within our statistical uncertainties.« less
  • We have simulated QCD using 2+1 flavors of domain wall quarks and the Iwasaki gauge action on a (2.74 fm){sup 3} volume with an inverse lattice scale of a{sup -1}=1.729(28) GeV. The up and down (light) quarks are degenerate in our calculations and we have used four values for the ratio of light quark masses to the strange (heavy) quark mass in our simulations: 0.217, 0.350, 0.617, and 0.884. We have measured pseudoscalar meson masses and decay constants, the kaon bag parameter B{sub K}, and vector meson couplings. We have used SU(2) chiral perturbation theory, which assumes only the upmore » and down quark masses are small, and SU(3) chiral perturbation theory to extrapolate to the physical values for the light quark masses. While next-to-leading order formulas from both approaches fit our data for light quarks, we find the higher-order corrections for SU(3) very large, making such fits unreliable. We also find that SU(3) does not fit our data when the quark masses are near the physical strange quark mass. Thus, we rely on SU(2) chiral perturbation theory for accurate results. We use the masses of the {omega} baryon, and the {pi} and K mesons to set the lattice scale and determine the quark masses. We then find f{sub {pi}}=124.1(3.6){sub stat}(6.9){sub syst} MeV, f{sub K}=149.6(3.6){sub stat}(6.3){sub syst} MeV, and f{sub K}/f{sub {pi}}=1.205(0.018){sub stat}(0.062){sub syst}. Using nonperturbative renormalization to relate lattice regularized quark masses to regularization independent momentum scheme masses, and perturbation theory to relate these to MS, we find m{sub ud}{sup MS}(2 GeV)=3.72(0.16){sub stat}(0.33){sub ren}(0.18){sub syst} MeV, m{sub s}{sup MS}(2 GeV)=107.3(4.4){sub stat}(9.7){sub ren}(4.9){sub syst} MeV, and m-tilde{sub ud} ratio m-tilde{sub s}=1 ratio 28.8(0.4){sub stat}(1.6){sub syst}. For the kaon bag parameter, we find B{sub K}{sup MS}(2 GeV)=0.524(0.010){sub stat}(0.013){sub ren}(0.025){sub syst}. Finally, for the ratios of the couplings of the vector mesons to the vector and tensor currents (f{sub V} and f{sub V}{sup T}, respectively) in the MS scheme at 2 GeV we obtain f{sub {rho}}{sup T}/f{sub {rho}}=0.687(27); f{sub K*}{sup T}/f{sub K*}=0.712(12), and f{sub {phi}}{sup T}/f{sub {phi}}=0.750(8)« less
  • We present results for the dependence of the residual mass of domain wall fermions (DWF) on the size of the fifth dimension and its relation to the density and localization properties of low-lying eigenvectors of the corresponding hermitian Wilson Dirac operator relevant to simulations of 2+1 flavor domain wall QCD. Using the DBW2 and Iwasaki gauge actions, we generate ensembles of configurations with amore » $$16^3\times 32$$ space-time volume and an extent of 8 in the fifth dimension for the sea quarks. We demonstrate the existence of a regime where the degree of locality, the size of chiral symmetry breaking and the rate of topology change can be acceptable for inverse lattice spacings $$a^{-1} \ge 1.6$$ GeV.« less
  • We present a high-statistics calculation of nucleon electromagnetic form factors in N{sub f}=2+1 lattice QCD using domain wall quarks on fine lattices, to attain a new level of precision in systematic and statistical errors. Our calculations use 32{sup 3}x64 lattices with lattice spacing a=0.084 fm for pion masses of 297, 355, and 403 MeV, and we perform an overdetermined analysis using on the order of 3600 to 7000 measurements to calculate nucleon electric and magnetic form factors up to Q{sup 2{approx_equal}}1.05 GeV{sup 2}. Results are shown to be consistent with those obtained using valence domain wall quarks with improved staggeredmore » sea quarks, and using coarse domain wall lattices. We determine the isovector Dirac radius r{sub 1}{sup v}, Pauli radius r{sub 2}{sup v} and anomalous magnetic moment {kappa}{sub v}. We also determine connected contributions to the corresponding isoscalar observables. We extrapolate these observables to the physical pion mass using two different formulations of two-flavor chiral effective field theory at one loop: the heavy baryon small scale expansion and covariant baryon chiral perturbation theory. The isovector results and the connected contributions to the isoscalar results are compared with experiment, and the need for calculations at smaller pion masses is discussed.« less
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