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Polarization contributions to the spin-dependence of the effective interaction in neutron matter

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 نشر من قبل Achim Schwenk
 تاريخ النشر 2003
  مجال البحث
والبحث باللغة English
 تأليف A. Schwenk




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We calculate the modification of the effective interaction of particles on the Fermi surface due to polarization contributions, with particular attention to spin-dependent forces. In addition to the standard spin-spin, tensor and spin-orbit forces, spin non-conserving effective interactions are induced by screening in the particle-hole channels. Furthermore, a novel long-wavelength tensor force is generated. We compute the polarization contributions to second order in the low-momentum interaction V_{low k} and find that the medium-induced spin-orbit interaction leads to a reduction of the 3P2 pairing gap for neutrons in the interior of neutron stars.

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