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Ghost propagator and the Coulomb form factor from the lattice

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 نشر من قبل Giuseppe Burgio
 تاريخ النشر 2012
  مجال البحث
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We calculate the Coulomb ghost propagator G(|p|) and the static Coulomb potential V_C(|r|) for SU(2) Yang-Mills theory on the lattice. In view of possible scaling violations related to deviations from the Hamiltonian limit we use anisotropic lattices to improve the temporal resolution. We find that the ghost propagator is infrared enhanced with an exponent kappa_gh ~ 0.5 while the Coulomb potential exhibits a string tension larger than the Wilson string tension, sigma_C ~ 2 sigma. This agrees with the Coulomb scaling scenario derived from the Gribov-Zwanziger confinement mechanism.

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