M. Oka

Theoretical overview of the pentaquarks

An overview of the current understanding of the pentaquark baryon spectroscopy will be given. After the seminal experimental report on the $\Theta^+$ discovery, numerous theoretical papers that attempt to explain its mass and quantum numbers have appeared. Yet no consensus is given even on its spin nor parity. The pentaquark spectroscopy is a treasure island for theorists, who reconsider their quark model picture of the hadrons and may find a new scheme of hadron spectroscopy. I will introduce studies based on quark models and on nonperturbative methods in quantum chromodynamics.