Query : 2015A&A...577A..40B

2015A&A...577A..40B - Astronomy and Astrophysics, volume 577A, 40-40 (2015/5-1)

A new quark-hadron hybrid equation of state for astrophysics. I. High-mass twin compact stars.


Abstract (from CDS):

We present a new microscopic hadron-quark hybrid equation of state model for astrophysical applications, from which compact hybrid star configurations are constructed. These are composed of a quark core and a hadronic shell with a first-order phase transition at their interface. The resulting mass-radius relations are in accordance with the latest astrophysical constraints. The quark matter description is based on a quantum chromodynamics (QCD) motivated chiral approach with higher-order quark interactions in the Dirac scalar and vector coupling channels. For hadronic matter we select a relativistic mean-field equation of state with density-dependent couplings. Since the nucleons are treated in the quasi-particle framework, an excluded volume correction has been included for the nuclear equation of state at suprasaturation density which takes into account the finite size of the nucleons. These novel aspects, excluded volume in the hadronic phase and the higher-order repulsive interactions in the quark phase, lead to a strong first-order phase transition with large latent heat, i.e. the energy-density jump at the phase transition, which fulfils a criterion for a disconnected third-family branch of compact stars in the mass-radius relationship. These twin stars appear at high masses (∼2M) that are relevant for current observations of high-mass pulsars. This analysis offers a unique possibility by radius observations of compact stars to probe the QCD phase diagram at zero temperature and large chemical potential and even to support the existence of a critical point in the QCD phase diagram.

Abstract Copyright:

Journal keyword(s): stars: neutron - stars: interiors - dense matter - equation of state

Simbad objects: 4

goto Full paper

goto View the references in ADS

Number of rows : 4
N Identifier Otype ICRS (J2000)
ICRS (J2000)
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2023
1 PSR J0348+0432 Psr 03 48 43.6363173480 +04 32 11.461921260           ~ 232 2
2 PSR J0437-47 Psr 04 37 15.7994581776 -47 15 08.544351636           DC 851 0
3 PSR J1614-2230 Psr 16 14 36.5070 -22 30 31.207           ~ 359 1
4 RX J1856.6-3754 Psr 18 56 35.11 -37 54 30.5     25.7     ~ 423 0

To bookmark this query, right click on this link: simbad:objects in 2015A&A...577A..40B and select 'bookmark this link' or equivalent in the popup menu


© Université de Strasbourg/CNRS

    • Contact