Roper Resonance in a Quark-diquark Model
نویسندگان
چکیده
We discuss a new description for the Roper resonance, the first nucleon excited state of JP = 1/2+, in a model of strong diquark correlations. Treating the scalarisoscalar and axial-vector–isovector diquarks as independent degrees of freedom, two states having nucleon quantum numbers are constructed. Due to the scalar and axial-vector nature of the diquarks, the two nucleon states have different internal structure of spin and isospin. This yields the mass splitting of order several hundreds MeV, and hence the two states are identified with the nucleon and Roper. We demonstrate this scenario in a simple two channel problem.
منابع مشابه
Structure of the Roper Resonance with Diquark Correlations
We study electromagnetic properties of the nucleon and Roper resonance in a chiral quark-diquark model including two kinds of diquarks needed to describe the nucleon: scalar and axial-vector diquarks. The nucleon and Roper resonance are described as superpositions of two quark-diquark bound states of a quark and a scalar diquark and of a quark and an axial-vector diquark. Electromagnetic form f...
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