Lattice Study of Low-lying Nonet Scalar Mesons in Quenched Approximation

Using lattice QCD simulation in the quenched approximation, we study the $\kappa$ meson, which is ^3P_0 in the quark model, and compare experimental and other lattice data. The $\kappa$ is the lowest scalar meson with strangeness and constitutes the scalar nonet. The obtained mass is much higher than the recent experimental value, and therefore the $\kappa (800)$ is difficult to consider as a simple two-body constituent-quark structure, and may have another unconventional structure.