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A link between measured neutron star masses and lattice QCD data

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 نشر من قبل Ignazio Bombaci Prof.
 تاريخ النشر 2012
  مجال البحث فيزياء
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We study the hadron-quark phase transition in neutron star matter and the structural properties of hybrid stars using an equation of state (EOS) for the quark phase derived with the field correlator method (FCM). We make use of the measured neutron star masses, and particularly the mass of PSR J1614-2230, to constrain the values of the gluon condensate $G_2$ which is one of the EOS parameter within the FCM. We find that the values of $G_2$ extracted from the mass measurement of PSR J1614-2230 are fully consistent with the values of the same quantity derived, within the FCM, from recent lattice quantum chromodynamics (QCD) calculations of the deconfinement transition temperature at zero baryon chemical potential. The FCM thus provides a powerful tool to link numerical calculations of QCD on a space-time lattice with neutron stars physics.

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