Isgur-Karl model revisited

We show how to match the Isgur-Karl model to the spin-flavor quark operator expansion used in the 1/Nc studies of the nonstrange negative parity L=1 excited baryons. Using the transformation properties of states and interactions under the permutation group S3 we are able to express the operator coef...

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Detalhes bibliográficos
Autores: Galeta, Leonardo Javier, Pirjol, Dan, Schat, Carlos Luis
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2009
País:Argentina
Recursos:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/60446
Acesso em linha:http://hdl.handle.net/11336/60446
Access Level:acceso abierto
Palavra-chave:1/Nc Expansion
Excited Baryons
Quark Model
Effective Theories
https://purl.org/becyt/ford/1.3
https://purl.org/becyt/ford/1
Descrição
Resumo:We show how to match the Isgur-Karl model to the spin-flavor quark operator expansion used in the 1/Nc studies of the nonstrange negative parity L=1 excited baryons. Using the transformation properties of states and interactions under the permutation group S3 we are able to express the operator coefficients as overlap integrals, without making any assumption on the spatial dependence of the quark wave functions. The general mass operator leads to parameter free mass relations and constraints on the mixing angles that are valid beyond the usual harmonic oscillator approximation. The Isgur-Karl model with harmonic oscillator wave functions provides a simple counterexample that demonstrates explicitly that the alternative operator basis for the 1/Nc expansion for excited baryons recently proposed by Matagne and Stancu is incomplete. © 2009 The American Physical Society.