2003/02/28 by Y. Nemoto, N. Nakajima, Hideo Matsufuru +3 · 2 citations
Physics and Astronomy · #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-lat #nucl-th
paper · pdf · doi:10.1103/physrevd.68.094505
published as Phys.Rev. D68 (2003) 094505 · 14 pages, 15 eps figures, version to appear in Phys. Rev. D. Discussions on the quenching effects are mainly modified
arxiv created 2003/09/07 · openalex publication_date 2003/11/21 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We investigate the negative-parity baryon spectra in quenched lattice QCD. We employ the anisotropic lattice with a standard Wilson gauge and O(a) improved Wilson quark actions at three values of lattice spacings with a renormalized anisotropy \ensuremathξ=a_\ensuremathσ/a_\ensuremathτ=4, where a_\ensuremathσ and a_\ensuremathτ are spatial and temporal lattice spacings, respectively. The negative-parity baryons are measured with the parity projection. In particular, we pay much attention to the lowest SU(3) flavor-singlet negative-parity baryon, which is assigned as the \ensuremathΛ(1405) in the quark model. For the flavor octet and decuplet negative-parity baryons, the calculated masses are close to the experimental values of corresponding lowest-lying negative-parity baryons. In contrast, the flavor-singlet baryon is found to be about 1.7 GeV, which is much heavier than the \ensuremathΛ(1405). Therefore it is difficult to identify the \ensuremathΛ(1405) to be the flavor-singlet three-quark state, which seems to support an interesting picture of the pentaquark (udsqq) state or the NK molecule for the \ensuremathΛ(1405).