Scalar meson in dynamical and partially quenched two-flavor QCD: lattice results and chiral loops

Abstract

This is an exploratory study of the lightest non-singlet scalar $q\bar{q}$ state on the lattice with two dynamical quarks. Domain Wall fermions are used for both sea and valence quarks on a 16^3*32 lattice with an inverse lattice spacing of 1.7 GeV. We extract the scalar meson mass 1.58(34) GeV from the exponential time-dependence of the dynamical correlators with $m_{val}=m_{sea}$ and N_f=2. Since this statistical error-bar from dynamical correlators is rather large, we analyze also the partially quenched lattice correlators with $m_{val}$ not equal $m_{sea}$. They are positive for $m_{val}>=m_{sea}$ and negative for $m_{val}<m_{sea}$. In order to understand this striking effect of partial quenching, we derive the scalar correlator within the Partially Quenched ChPT and find it describes lattice correlators well. The leading unphysical contribution in Partially Quenched ChPT comes from the exchange of the two pseudoscalar fields and is also positive for $m_{val}>=m_{sea}$ and negative for $m_{val}<m_{sea}$ at large t. After the subtraction of this unphysical contribution from the partially quenched lattice correlators, the correlators are positive and exponentially falling. The resulting scalar meson mass 1.51(19) GeV from the partially quenched correlators is consistent with the dynamical result and has appreciably smaller error-bar.

arXiv comment23 pages, 8 figures

References in corpus (31)

• A Method for Simulating Chiral Fermions on the Lattice
• Axial symmetries in lattice QCD with Kaplan fermions
• The QCD spectrum with three quark flavors
• Scalar mesons above and below 1 GeV
• Experimental evidence for a light and broad scalar resonance in $D^{+}\to {\pi }^{-}{\pi }^{+}{\pi }^{+}$ decay
• Partially Quenched Gauge Theories and a Application to Staggered Fermions
• Light Hadron Spectroscopy with Two Flavors of Dynamical Quarks on the Lattice
• Dalitz Plot Analysis of the Decay D^+ --> K^- pi^+ pi^+ and Indication of a Low-Mass Scalar K pi Resonance
• Insight into the Scalar Mesons from a Lattice Calculation
• Scalar Quarkonium Masses and Mixing with the Lightest Scalar Glueball
• Physical Results from Unphysical Simulations
• Partially quenched chiral perturbation theory without ${\Phi }_0$
• Quenched Lattice QCD with Domain Wall Fermions and the Chiral Limit
• Enhanced chiral logarithms in partially quenched QCD
• Non-perturbative Renormalisation of Domain Wall Fermions: Quark Bilinears
• Mixing of scalar glueballs and flavour-singlet scalar mesons
• Scalar Particles in Lattice QCD
• QCD with domain wall quarks
• Domain wall quarks and kaon weak matrix elements
• Domain wall fermions with improved gauge actions
• Chiral Loops and Ghost States in the Quenched Scalar Propagator
• Chiral properties of domain-wall quarks in quenched QCD
• Universality and scaling behavior of RG gauge actions
• Chiral Effective Lagrangian and Quark Masses
• Chiral Lagrangian Parameters for Scalar and Pseudoscalar Mesons
• Masses of singlet and non-singlet 0++ particles
• Quenched scalar meson correlator with Domain Wall Fermions
• Dynamical Domain Wall Fermions
• Lattice QCD with dynamical domain wall quarks
• Scalar Mesons as qbar^2 q^2? Insight from the Lattice
• Lattice study of "f${}_0$(600) or $\sigma$"

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• The role of the double pole in lattice QCD with mixed actions
• Derivative sources in lattice spectroscopy of excited light-quark mesons
• Discretization effects and the scalar meson correlator in mixed-action lattice simulations
• Strategy to find the two $\Lambda (1405)$ states from lattice QCD simulations
• Lattice Study of Low-lying Nonet Scalar Mesons in Quenched Approximation
• Understanding masses of $c\bar{s}$ states in Regge phenomenology
• The pion-pion Interaction in the rho Channel in Finite Volume
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• Excited Scalar and Pseudoscalar Mesons in the Extended Linear Sigma Model
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• eta' meson From Two Flavor Dynamical Domain Wall Fermions
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• Roper State from Overlap Fermions
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• A Mixed Action Analysis of $\eta$ and ${\eta }^{\prime }$ Mesons
• Flavor symmetry breaking in lattice QCD with a mixed action
• Branching Ratios and CP Violations of B \to K_0^*(1430) K^* Decays in the pQCD Approach
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