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تسجيل مستخدم جديدExotic Quark Structure of Lambda(1405) in QCD Sum Rule
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A new analysis is performed in QCD sum rule for the lightest negative parity baryon Lambda (1405). Mixings of three-quark and five-quark Fock components are taken into account. Terms containing up to dimension 12 condensates are computed in the operator product expansion. It is found that the sum rule gives much stronger coupling of Lambda* to the five-quark operator so that the five-quark components occupy about 90% of Lambda (1405).
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Five-quark (5Q) picture of Lambda(1405) is studied using quenched lattice QCD with an exotic 5Q operator of Nbar{K} type. To discreminate mere Nbar{K} and Sigmapi scattering states, Hybrid Boundary Condition (HBC), a flavor-dependent boundary conditi
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