We are comprehensively measuring the production and decay of exotic baryons such as pentaquark Θ+, consisting of five or more quarks, and Λ(1405) which is a candidate of molecular-type meson-baryon resonances containing s quark, in order to clarify the properties (mass, decay width, internal degree of freedom(spin, isospin, parity)) of these exotics. Through hitherto-unidentified exotic states of hadrons, we are finding a new picture of hadron formation beyond that of the simple quark model. Furthermore, we are enriching our understanding of the constituent quarks of hadrons, as well as the quark-antiquark and quark-quark correlations so that we can better understand the quark confinement and mass generation mechanism of hadrons.
We are comprehensively measuring and investigating the production and decay of exotic baryons to explore new hadronic states with polarized photon beams provided by the Laser Electron Photon beam line facility at SPring-8 (LEPS) and hadron beams provided by J-PARC. Because the coupling strengths of exotic hadrons to the production and decay channels depend on the properties of the hadrons, use of different beams, introducing different kinematics and internal degrees of freedom to the reaction process, is particularly useful for identifying the properties of exotic hadrons.
In this research project, we are working on the following topics:
Related link: LEPS - Laser Electron Photon Experiment at SPring-8