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arXiv · 0707.0079

Five-quark picture of Lambda(1405) in anisotropic lattice QCD

Noriyoshi Ishii·Takumi Doi·Makoto Oka·Hideo Suganuma
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Abstract

Five-quark (5Q) picture of Lambda(1405) is studied using quenched lattice QCD with an exotic 5Q operator of N\bar{K} type. To discreminate mere N\bar{K} and Σπscattering states, Hybrid Boundary Condition (HBC), a flavor-dependent boundary condition, is imposed on the quark fields along spatial direction. 5Q mass m_{5Q}\simeq 1.89 GeV is obtained after the chiral extrapolation to the physical quark mass region, which is too heavy to be identified with Lambda(1405). Then, Lambda(1405) seems neither a pure 3Q state nor a pure 5Q state, and therefore we present an interesting possibility that Lambda(1405) is a mixed state of 3Q and 5Q states.

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Noriyoshi Ishii, Takumi Doi, Makoto Oka, Hideo Suganuma. 2007-06-30. Five-quark picture of Lambda(1405) in anisotropic lattice QCD. https://doi.org/10.1143/ptps.168.598

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