A study of Theta(+) (udud(s)over-bar) in lattice QCD

作者：Chin TW^*; Hsieh TH

来源：Nuclear Physics B - Proceedings Supplements, 2005, 140: 272-274.

DOI：10.1016/j.nuclphysbps.2004.11.188

We investigate the mass spectrum of the pentaquark baryon (udud (s) over bar) in quenched lattice QCD with exact chiral symmetry. Using 3 different interpolating operators, we measure the 3 x 3 correlation matrix and obtain the eigenvalues A(+/-) (t) with +/- parity. For odd parity states, A(-) (t) deviates from pure exponential decay even at large t, which implies that it cannot be a resonance with narrow decay width, thus is ruled out as a candidate of Theta(+) (1540). For even parity states, they behave like usual resonances seen in quenched lattice QCD, and the mass of the lowest lying J(P) = 1/2(+) state is determined to be 1583 +/- 121 MeV.

• 出版日期2005-3