Importance of closed quark loops for lattice QCD studies of tetraquarks

Abstract

To investigate the light scalar tetraquark candidate $a_0(980)$ (quantum numbers $J^P=0^{+}$), a correlation matrix including a variety of two- and four-quark interpolating operators has to be computed. We discuss efficient techniques to compute the elements of this correlation matrix, in particular diagrams with closed quark loops. Furthermore, we present evidence that such diagrams are not negligible given our precision, and their contribution is essential to obtain physically meaningful results. In particular, we find indications of the existence of an "additional" state around the two-particle thresholds of $K+\bar{K}$ and $\eta +\pi$, which could correspond to the $a_0(980)$ meson.

7 pages, 5 figures, talk given at the 34th International Symposium on Lattice Field Theory (Lattice 2016), July 24-30 2016, Southampton, UK

References in corpus (10)

• Lattice study of light scalar tetraquarks with I=0,2,1/2,3/2: are sigma and kappa tetraquarks?
• Scalar Meson Spectroscopy with Lattice Staggered Fermions
• A novel analysis method for excited states in lattice QCD - the nucleon case
• Derivative sources in lattice spectroscopy of excited light-quark mesons
• Lattice QCD study of four-quark components of the isosinglet scalar mesons: Significance of disconnected diagrams
• Investigation of the tetraquark candidate $a_0(980)$: technical aspects and preliminary results
• Recent progress on light scalars: from confusion to precision using dispersion theory
• Lattice investigation of the tetraquark candidates a0(980) and kappa
• Simulations of light scalar mesons on the lattice and related difficulties
• Analysis of the scalar mesons on the Lattice

Cited by in corpus (1)

• Using a new analysis method to extract excited states in the scalar meson sector