The Negative-parity spin-1/2 baryon spectrum from lattice QCD and effective theory

格子QCD及び有効理論によるスピン1/2負パリティバリオン

Pavao, R.*; Gubler, P. ; Fernandez-Soler, P.*; Nieves, J.*; 岡 眞   ; 高橋 徹*

Pavao, R.*; Gubler, P.; Fernandez-Soler, P.*; Nieves, J.*; Oka, Makoto; Takahashi, Toru*

The spectrum of the negative-parity spin-1/2 baryons is studied using lattice QCD and hadronic effective theory in a unitarized coupled-channel framework. A direct comparison between the two approaches is possible by considering the hadronic effective theory in a finite volume and with hadron masses and mesonic decay constants that correspond to the situation studied on the lattice. Comparing the energy level spectrum and flavor decompositions of the individual states, itis found that the lowest two states extracted from lattice QCD can be identified with one of the two (1405)-poles and the (1670) resonance. The quark mass dependences of these two lattice QCD levels are in good agreement with their effective theory counterparts.