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تسجيل مستخدم جديدBayesian analysis of multimessenger M-R data with interpolated hybrid EoS
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We introduce a family of equations of state (EoS) for hybrid neutron star (NS) matter that is obtained by a two-zone parabolic interpolation between a soft hadronic EoS at low densities and a set of stiff quark matter EoS at high densities within a finite region of chemical potentials $mu_H < mu < mu_Q$. Fixing the hadronic EoS as the APR one and chosing the color-superconductiong, nonlocal NJL model with two free parameters for the quark phase, we perform Bayesian analyses with this two-parameter family of hybrid EoS. Using three different sets of observational constraints that include the mass of PSR J0740+6620, the tidal deformability for GW170817 and the mass-radius relation for PSR J0030+0451 from NICER as obligatory (set 1), while set 2 uses the possible upper limit on the maximum mass from GW170817 as additional constraint and set 3 instead the possibility that the lighter object in the asymmetric binary merger GW190814 is a neutron star. We confirm that in any case the quark matter phase has to be color superconducting with the dimensionless diquark coupling approximately fulfilling the Fierz relation $eta_D=0.75$ and the most probable solutions exhibiting a proportionality between $eta_D$ and $eta_V$, the coupling of the repulsive vector interaction that is required for a sufficiently large maximum mass. We anticipate the outcome of the NICER radius measurement on PSR J0740+6220 as a fictitious constraint and find evidence for claiming that GW190814 was a binary black hole merger if the radius will be 11 km or less.
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