Lattice QCD study of four-quark components of the isosinglet scalar mesons: Significance of disconnected diagrams

Abstract

We study the possible significance of four-quark states in the iso-singlet scalar mesons ($J^{PC}=0^{++}$, $I=0$) by performing two-flavor full lattice QCD simulations on an $8^3\times 16$ lattice using the improved gauge action and the clover-improved Wilson quark action. In particular, we evaluate the propagators of molecular and tetra-quark operators together with singly disconnected diagrams. In the computation of the singly disconnected diagrams we employ the $Z_2$-noise method with the truncated eigenmode approach. We show that the quark loops given by the disconnected diagrams play an essential role in propagators of tetraquark and molecular operators.

arXiv comment18 pages, 7 figures

References in corpus (28)

• Observation of a New Narrow Charmonium State in Exclusive B+-->K+ pi+pi- J/psi Decays
• Observation of a narrow charmonium-like state in exclusive B+ -> K+ pi+pi- J/psi decays
• Observation of two charged bottomonium-like resonances in Y(5S) decays
• Glueball Spectrum and Matrix Elements on Anisotropic Lattices
• Exotica
• Observation of a resonance-like structure in the pi^+- psi' mass distribution in exclusive B-->K pi^+- psi' decays
• Measurement of e^+e^- to pi^+pi^-J/psi Cross Section via Initial State Radiation at Belle
• Practical all-to-all propagators for lattice QCD
• Insight into the Scalar Mesons from a Lattice Calculation
• Phase structure and critical temperature of two-flavor QCD with a renormalization group improved gauge action and clover improved Wilson quark action
• On the low fermionic eigenmode dominance in QCD on the lattice
• Evidence for diquarks in lattice QCD
• Mixing of scalar glueballs and flavour-singlet scalar mesons
• Scalar Particles in Lattice QCD
• Scalar Mesons a0(1450) and sigma(600) from Lattice QCD
• Lattice study of light scalar tetraquarks with I=0,2,1/2,3/2: are sigma and kappa tetraquarks?
• A lattice study of the masses of singlet 0++ mesons
• Properties of light scalar mesons from lattice QCD
• Lattice investigation of the scalar mesons a_0(980) and κ using four-quark operators
• A lattice study of light scalar tetraquarks
• Lattice Study of Low-lying Nonet Scalar Mesons in Quenched Approximation
• Tetraquarks, hadronic molecules, meson-meson scattering and disconnected contributions in lattice QCD
• Tetra-Quark Resonances in Lattice QCD
• Flavour singlet pseudoscalar masses in N_f = 2 QCD
• QCD with two light dynamical chirally improved quarks: Mesons
• Scalar and Vector 4Q Systems in Anisotropic Lattice QCD
• Lowest-lying Tetra-Quark Hadrons in Anisotropic Lattice QCD
• The static-light baryon spectrum from twisted mass lattice QCD

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• From controversy to precision on the sigma meson: a review on the status of the non-ordinary $f_0(500)$ resonance
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• Isoscalar $\pi \pi ,K\overline{K},\eta \eta$ scattering and the $\sigma ,f_0,f_2$ mesons from QCD
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• The light scalars: four- vs. two-quark states in the complex energy plane from Bethe-Salpeter equations
• Inverse Mass Hierarchy of Light Scalar Mesons Driven by Anomaly-Induced Flavor Breaking
• Investigating efficient methods for computing four-quark correlation functions
• The sigma meson from QCD sum rules for large-$N_c$ Regge spectra
• Ultra-light Glueballs in Quark-Gluon Plasma
• Non-perturbative Analysis of Various Mass Generation by Gluonic Dressing Effect with the Schwinger-Dyson Formalism in QCD
• Observation of $D^{+}\to f_0(500){\mu }^{+}{\nu }_{\mu }$ and study of $D^{+}\to {\pi }^{+}{\pi }^{-}{\ell }^{+}{\nu }_{\ell }$ decay dynamics
• Photoproduction of the scalar mesons $f_0(500)$ and $f_0(980)$ off the nucleon
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