Axial Vector Tetraquark with Two s-quarks

Abstract

Possibility of an axial vector isoscalar tetraquark $ud\bar{s}\bar{s}$ is discussed. If a $f_1$ meson in the mass region $1.4-1.5$ GeV consists of four quarks $ns\bar{n}\bar{s}$, the mass of the isoscalar $ud\bar{s}\bar{s}$(${\vartheta }^{+}$-meson) state with $J^P=1^{+}$ is expected to be lower than that of the $f_1$ meson. Within a flux-tube quark model, a possible resonant state of $ud\bar{s}\bar{s}(J^P=1^{+})$ is suggested to appear at $\sim$ 1.4 GeV with the width $\mathcal{O}(20\sim 50)$ MeV. We propose that the ${\vartheta }^{+}$-meson is the good candidate for the tetraquark search, which would be observed in the $K^{+}{K}^{+}{\pi }^{-}$ decay channel.

prepared for Yukawa International Seminars "New Frontiers in QCD" (YKIS2006), Nov. 20-Dec. 8, 2006, Kyoto, Japan, to appear in Prog. Theor. Phys. Suppl