Hadron Physics at J-PARC

An outline is explained for hadron-physics projects at J-PARC, which is considered to be one of the flagship facilities in hadron physics from 2008. The facility provides an intensity frontier with 50 GeV proton beam for nuclear and particle physics. It could cover a wide range of hadron physics from strongly interacting many-body systems with an extended hadronic degree of freedom, strangeness, to new forms of hadrons and hadronic matters. These studies lead not only to create innovative fields of hadron physics but also, possibly, to understand fundamental interactions because of recent progress on AdS/CFT correspondence. At the first stage of the J-PARC operation, hadron topics are mainly on strangeness nuclear physics such as hypernuclei, kaonic nuclei, and possible pentaquark hadrons. Then, the studies could be extended to exotic hadron searches, chiral dynamics in nuclear medium, structure functions, hard exclusive processes, hadron physics in neutrino scattering, and spin structure of the nucleon. With major upgrades of the facility, extensive studies could be done for the nucleon spin, heavy-ion physics, and hadron physics at a high-energy neutrino factory.