Hybrid stars are compatible with recent astrophysical observations
Abstract
Compact stars (CS) are stellar remnants of massive stars. Inside CSs the density is so high that matter is in subatomic form composed of nucleons. With an increase of density of matter toward the center of the objects, other degrees of freedom like hyperons, heavier nonstrange baryons, meson condensates may appear. Not only that, at higher densities the nucleons may get decomposed into quarks and form deconfined strange quark matter (SQM). If it is so then CSs may contain SQM in the core surrounded by nucleonic matter forming hybrid stars (HSs). However, the nature and composition of matter inside CSs can only be inferred from the astrophysical observations of these CSs. Recent astrophysical observations in terms of CS mass-radius (M-R) relation and gravitational wave (GW) observation indicate that the matter should be soft in the intermediate density range and stiff enough at higher density range to attain the maximum possible mass above 2 M⊙ which is not compatible with pure hadronic equations of states (EOSs). Consequently, we study the HS properties with different models of SQM and find that within vector bag model considering density dependent bag parameter, the model goes well with the astrophysical observations so far.
- Publication:
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Physical Review D
- Pub Date:
- March 2023
- DOI:
- arXiv:
- arXiv:2303.06387
- Bibcode:
- 2023PhRvD.107f3024K
- Keywords:
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- Astrophysics - High Energy Astrophysical Phenomena
- E-Print:
- 12 pages, 9 figures