Lattice study of light scalar tetraquarks with I=0,2,1/2,3/2: Are {sigma} and {kappa} tetraquarks?
- Department of Physics, University of Ljubljana and Jozef Stefan Institute, Ljubljana (Slovenia)
- Department of Physics and Astronomy, University of Kentucky, Lexington, Kentucky 40506 (United States)
- Institut fuer Physik, FB Theoretische Physik, Universitaet Graz, A-8010 Graz (Austria)
- Department of Theoretical Physics, Tata Institute of Fundamental Research, Mumbai (India)
- TRIUMF, 4004 Wesbrook Mall Vancouver, British Columbia V6T 2A3 (Canada)
We investigate whether the lightest scalar mesons {sigma} and {kappa} have a large tetraquark component qqqq, as is strongly supported by many phenomenological studies. A search for possible light tetraquark states with J{sup PC}=0{sup ++} and I=0,2,1/2,3/2 on the lattice is presented. We perform the two-flavor dynamical simulation with chirally improved quarks and the quenched simulation with overlap quarks, finding qualitative agreement between both results. The spectrum is determined using the generalized eigenvalue method with a number of tetraquark interpolators at the source and the sink, and we omit the disconnected contractions. The time dependence of the eigenvalues at the finite temporal extent of the lattice is explored also analytically. In all the channels, we unavoidably find the lowest scattering states {pi}(k){pi}(-k) or K(k){pi}(-k) with back-to-back momentum k=0,2{pi}/L,.... However, we find an additional light state in the I=0 and I=1/2 channels, which may be interpreted as the observed resonances {sigma} and {kappa} with a sizable tetraquark component. In the exotic repulsive channels I=2 and I=3/2, where no resonance is observed, we find no light state in addition to the scattering states.
- OSTI ID:
- 21503815
- Journal Information:
- Physical Review. D, Particles Fields, Vol. 82, Issue 9; Other Information: DOI: 10.1103/PhysRevD.82.094507; (c) 2010 American Institute of Physics; ISSN 0556-2821
- Country of Publication:
- United States
- Language:
- English
Similar Records
I{sup G}J{sup PC}=1{sup -}1{sup -+} tetraquark states
Quark mass dependence of light resonances and phase shifts in elastic {pi}{pi} and {pi}K scattering