Variation of the <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi mathvariant="normal">Δ</mml:mi></mml:math> baryon mass and hybrid star properties in static and rotating conditions
Debashree Sen
Abstract
The possible conditions for hadron-quark phase transition in hybrid star cores are investigated in the present work. For the hadronic matter part the effective chiral model is adopted. Exotic baryonic degrees like hyperons and the $\mathrm{\ensuremath{\Delta}}$ baryons are also taken into account. As $\mathrm{\ensuremath{\Delta}}\mathrm{s}$ possess Breit-Wigner mass distribution ($1232\ifmmode\pm\else\textpm\fi{}120$ MeV), the hadronic equation of state is obtained by varying the mass of the $\mathrm{\ensuremath{\Delta}}$ baryons in this range. For the quark phase the MIT Bag model is chosen with repulsive effects of the unpaired quarks. Phase transition is achieved using Gibbs construction and the gross properties of the resultant hybrid star are calculated in both static and rotating conditions and compared with the various constraints on them from different observational and empirical perspectives. The work presents a thorough study of the phase transition properties like the critical density of the appearance of quarks, the density range for the persistence of the mixed phase, and the population of different hadrons and quarks in hybrid star matter. The hybrid star properties, calculated in both static and rotating conditions, are found to be consistent with the bounds on them from different perspectives.