Physical results from 2+1 flavor domain wall QCD and SU(2) chiral perturbation theory

Journal Article · Mon Dec 01 00:00:00 EST 2008 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.78.114509· OSTI ID:21251030

Allton, C ^[1]; Antonio, D J; Boyle, P A; Hart, A; Kennedy, A D; Kenway, R D; Pendleton, B J; Tweedie, R J; Wennekers, J; Zanotti, J M ^[2]; Aoki, Y; Dawson, C ^[3]; Blum, T ^[3]; Christ, N H; Cohen, S D; Li, M; Li, S; Lin, M F; Mawhinney, R D ^[4]; Clark, M A ^[5]

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1. Department of Physics, Swansea University, Swansea SA2 8PP (United Kingdom)
2. SUPA, School of Physics, The University of Edinburgh, Edinburgh EH9 3JZ (United Kingdom)
3. RIKEN-BNL Research Center, Brookhaven National Laboratory, Upton, New York 11973 (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)

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 up 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)

• OSTI ID: 21251030
• Journal Information: Physical Review. D, Particles Fields, Vol. 78, Issue 11; Other Information: DOI: 10.1103/PhysRevD.78.114509; (c) 2008 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BAG MODEL
CHIRALITY
CORRECTIONS
COUPLING
FLAVOR MODEL
GEV RANGE 01-10
KAONS
LATTICE FIELD THEORY
MEV RANGE 100-1000
OMEGA BARYONS
PARTICLE DECAY
PERTURBATION THEORY
QUANTUM CHROMODYNAMICS
QUARKS
RENORMALIZATION
SIMULATION
SU-2 GROUPS
SU-3 GROUPS
VECTOR CURRENTS
VECTOR MESONS