Possibility of a new narrow resonance near the threshold

閾値近傍における新しい共鳴の可能性

谷田 聖   

Tanida, Kiyoshi

Evidence for a narrow resonance at a mass of about 1665 MeV (just above the combined mass of the ground state plus the meson) has been seen in the mass of the Dalitz plot for decay at the Belle experiment. Additional evidence for this resonance is found in the partial-wave analysis (PWA) of data on reactions done independently by several groups, driven by angular distributions of the reaction by the Crystal Ball collaboration. If a narrow resonance exists at this mass, then the conventional quark model cannot explain it, and a possible explanation is that it is a crypto-exotic baryon with a dominant meson-baryon component to its wave function. Therefore we have proposed a definitive experiment for , using the newly built hypTPC detector to establish the existence of the proposed narrow and determine its spin and parity in just two weeks of beamtime at J-PARC (E72). We will discuss these evidences for the proposed resonance and introduce the E72 experiment.