Study of pentaquarks on the lattice with overlap fermions

Abstract

We present a quenched lattice QCD calculation of spin-1/2 five-quark states with uudds̅ quark content for both positive and negative parities. We do not observe any bound pentaquark state in these channels for either I=0 or I=1. The states we found are consistent with KN scattering states which are checked to exhibit the expected volume dependence of the spectral weight. The results are based on overlap-fermion propagators on two lattices, 12³×28 and 16³×28, with the same lattice spacing of 0.2 fm, and pion mass as low as ∼180 MeV.