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Renormalization group and scattering-equivalent Hamiltonians on a coarse momentum grid

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 نشر من قبل Maria Gomez-Rocha
 تاريخ النشر 2020
  مجال البحث
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We consider the $pipi$-scattering problem in the context of the Kadyshevsky equation. In this scheme, we introduce a momentum grid and provide an isospectral definition of the phase-shift based on the spectral shift of a Chebyshev angle. We address the problem of the unnatural high momentum tails present in the fitted interactions which reaches energies far beyond the maximal center-of-mass energy of $sqrt{s}=1.4$ GeV. It turns out that these tails can be integrated out by using a block-diagonal generator of the SRG.



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