Lowest-lying Tetra-Quark Hadrons in Anisotropic Lattice QCD
| Autor: | Loan, Mushtaq, Luo, Zhi-Huan, Lam, Yu Yiu |
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| Rok vydání: | 2008 |
| Předmět: | |
| Zdroj: | Eur. Phys. J. C 57, 579 (2008) |
| Druh dokumentu: | Working Paper |
| DOI: | 10.1140/epjc/s10052-008-0689-0 |
| Popis: | We present a detailed study of lowest-lying $q^{2}\bar{q}^{2}$ hadrons in quenched improved anisotropic lattice QCD. Using the $\pi\pi$ and diquark-antidiquark local and smeared operators, we attempt to isolate the signal for $I(J^{P})=0(0^{+}), 2(0^{+})$ and $1(1^{+})$ states in two flavour QCD. In the chiral limit of light-quark mass region, the lowest scalar $4q$ state is found to have a mass, $m^{I=0}_{4q}=927(12)$ MeV, which is slightly lower than the experimentally observed $f_{0}(980)$. The results from our variational analysis do not indicate a signature of a tetraquark resonance in I=1 and I=2 channels. After the chiral extrapolation the lowest $1(1^{+})$ state is found to have a mass, $m^{I=1}_{4q}=1358(28)$ MeV. We analysed the static $4q$ potential extracted form a tetraquark Wilson loop and illustrated the behaviour of the $4q$ state as a bound state, unbinding at some critical diquark separation. From our analysis we conclude that scalar $4q$ system appears as a two-pion scattering state and that there is no spatially-localised $4q$ state in the light-quark mass region. Comment: 9 pages, 10 figures |
| Databáze: | arXiv |
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