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What is the right formalism to search for resonances? II. The pentaquark chain

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 نشر من قبل Alessandro Pilloni
 تاريخ النشر 2018
  مجال البحث
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We discuss the differences between several partial-wave analysis formalisms used in the construction of three-body decay amplitudes involving fermions. Specifically, we consider the decay Lambda_b -> psi p K- , where the hidden charm pentaquark signal has been reported. We analyze the analytical properties of the amplitudes and separate kinematical and dynamical singularities. The result is an amplitude with the minimal energy dependence compatible with the S-matrix principles.



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