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Regge trajectories of Excited Baryons, quark-diquark models and quark-hadron duality

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 نشر من قبل Enrique Ruiz Arriola
 تاريخ النشر 2017
  مجال البحث
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The parton model relations in conjunction with quark-hadron duality in deep inelastic scattering suggests an asymptotic dominance of quark-diquark type of baryonic excited states with a radial Regge uniformly distributed mass squared spectrum $M_{n}^2 = mu^2 n + M_0^2$. We argue that this points to a lineary quark-diquark confining potential. We analyze the radial ($n$) and angular-momentum ($J$) Regge trajectories for all light-quark states with baryon number one listed in the 2016 edition of the Particle Data Tables. The parameters of the mass squared trajectories are obtained by linear regression assuming $Delta M_n^2 sim M_n Gamma_n $ weighted with the width $Gamma_n$ of the resonance and the error analysis is carried out accordingly.

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