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On the resonance spectra of particle-unstable light nuclei with a Sturmian approach that preserves the Pauli principle

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 نشر من قبل Luciano Canton
 تاريخ النشر 2006
  مجال البحث
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The fundamental ingredients of the MCAS (multi-channel algebraic scattering) method are discussed. The main feature, namely the application of the sturmian theory for nucleon-nucleus scattering, allows solution of the scattering problem given the phenomenological ingredients necessary for the description of weakly-bound (or particle-unstable) light nuclear systems. Currently, to describe these systems, we use a macroscopic, collective model. Analyses show that the couplings to low-energy collective-core excitations are fundamental but they are physically meaningful only if the constraints introduced by the Pauli principle are taken into account. For this we introduce in the nucleon-nucleus system the Orthogonalizing Pseudo-Potential formalism, extended to collective excitations of the core. The formalism leads one to discuss a new concept, Pauli hindrance, which appears to be important especially to understand the structure of weakly-bound and unbound systems.



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