Pentaquark interpolating fields in lattice QCD

Full text: Claims about the discovery of the theta-plus pentaquark with strangeness = +1 has inspired tremendous interest in the field of high energy physics. As the only 'first principles' approach for studying nonperturbative QCD, lattice QCD provides a unique insight into the properties of a five quark state. Using the computational power of the APAC national facility's alpha cluster our study is at the leading edge of hadronic physics in lattice QCD. We discuss various pentaquark interpolating fields suitable for lattice QCD simulations. Using a number of interpolating fields we attempt to isolate a signal for a five-quark resonance. Calculations are performed using FLIC fermions in the quenched approximation. We observe that the pentaquark interpolating fields we studied did not give us access to a five quark bound state but rather a Nucleon plus Kaon state. Copyright (2005) Australian Institute of Physics