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Pion-less effective field theory for atomic nuclei and lattice nuclei

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 نشر من قبل Thomas Papenbrock
 تاريخ النشر 2017
  مجال البحث
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We compute the medium-mass nuclei $^{16}$O and $^{40}$Ca using pionless effective field theory (EFT) at next-to-leading order (NLO). The low-energy coefficients of the EFT Hamiltonian are adjusted to experimantal data for nuclei with mass numbers $A=2$ and $3$, or alternatively to results from lattice quantum chromodynamics (QCD) at an unphysical pion mass of 806 MeV. The EFT is implemented through a discrete variable representation in the harmonic oscillator basis. This approach ensures rapid convergence with respect to the size of the model space and facilitates the computation of medium-mass nuclei. At NLO the nuclei $^{16}$O and $^{40}$Ca are bound with respect to decay into alpha particles. Binding energies per nucleon are 9-10 MeV and 30-40 MeV at pion masses of 140 MeV and 806 MeV, respectively.



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