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$pipi$ scattering from a similarity renormalization group perspective

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 نشر من قبل Maria Gomez-Rocha
 تاريخ النشر 2019
  مجال البحث
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A Wilsonian approach based on the Similarity Renormalization Group to $pipi$ scattering is analyzed in the $JI=$00, 11 and 02 channels in momentum space up to a maximal CM energy of $sqrt{s}=1.4$ GeV. We identify the Hamiltonian by means of the 3D reduction of the Bethe-Salpeter equation in the Kadyschevsky scheme. We propose a new method to integrate the SRG equations based in the Crank-Nicolson algorithm with a single step finite difference so that isospectrality is preserved at any step of the calculations. We discuss issues on the high momentum tails present in the fitted interactions hampering calculations.



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