Maximally stiff equations of state and the structure of hybrid stars


Δημοσιευμένα: Ιουν 2, 2025
Pavlos Laskos-Patkos
Georgios A. Lalazissis
Sibo Wang
Jie Meng
Peter Ring
Charalambos C. Moustakidis
Περίληψη

The simultaneous reconciliation of the 1σ estimations on the mass (M) and radius (R) of the PSR J0030+0451 pulsar and the HESS J1731-347 remnant requires a region in the M-R plane where the slope dM/dR is positive. The latter reflects that the equation of state (EOS) should stiffen as the density increases, which requires a sufficiently large value for the speed of sound in dense matter. However, based on different theoretical assumptions, the sound velocity manifests an upper bound leading to a constraint on how stiff the resulting EOS can be. In the present contribution, we present our recent work on the possible simultaneous explanation of the aforementioned measurements in the context of hybrid EOSs, by describing the high-density phase as maximally incompressible (considering different suggestions for the upper speed of sound bound). A relevant discussion on possible constraints on the properties of first order transitions is also included.

Λεπτομέρειες άρθρου
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Αναφορές
J. Schaffner-Bielich, Compact Star Physics (Cambridge University Press, Cambridge, England, 2020); doi: 10.1017/9781316848357 DOI: https://doi.org/10.1017/9781316848357
T.E. Riley, et al., Astrophys. J. Lett. 887, L21 (2019); doi: 10.3847/2041-8213/ab481c DOI: https://doi.org/10.3847/2041-8213/ab481c
M.C. Miller, et al., Astrophys. J. Lett. 887, L24 (2019); doi:10.3847/2041-8213/ab50c5 DOI: https://doi.org/10.3847/2041-8213/ab50c5
J.-E. Christian and J. Schaffner-Bielich, Astrophys. J. Lett. 894, L8 (2020); doi: 10.3847/2041-8213/ab8af4 DOI: https://doi.org/10.3847/2041-8213/ab8af4
V. Doroshenko, et al., Nat. Astron. 6, 1444 (2022); doi: 10.1038/s41550-022-01800-1 DOI: https://doi.org/10.1038/s41550-022-01800-1
F. Di Clemente, et al., Astrophys. J. 967, 159 (2024); doi: 10.3847/1538-4357/ad445b DOI: https://doi.org/10.3847/1538-4357/ad445b
J.E. Horvath et al., Astron. Astrophys. 672, L11 (2023); doi: 10.1051/0004-6361/202345885 DOI: https://doi.org/10.1051/0004-6361/202345885
P.T. Oikonomou and Ch.C. Moustakidis, Phys. Rev. D 108, 063010 (2023); doi: 10.1103/PhysRevD.108.063010 DOI: https://doi.org/10.1103/PhysRevD.108.063010
V. Sagun, et al., Astrophys. J. 958, 49 (2023); doi: 10.3847/1538-4357/acfc9e DOI: https://doi.org/10.3847/1538-4357/acfc9e
P. Laskos-Patkos, et al., Phys. Rev. D 109, 063017 (2024); doi: 10.1103/PhysRevD.109.063017 DOI: https://doi.org/10.1103/PhysRevD.109.063017
L. Brodie and A. Haber, Phys. Rev. C 108, 025806 (2023); doi: 10.1103/PhysRevC.108.025806 DOI: https://doi.org/10.1103/PhysRevC.108.025806
J.J. Li and A. Sedrakian, Phys. Lett. B 844, 138062 (2023); doi: 10.1016/j.physletb.2023.138062 DOI: https://doi.org/10.1016/j.physletb.2023.138062
S. Kubis, et al., Phys. Rev. C 108, 045803 (2023); doi: 10.1103/PhysRevC.108.045803 DOI: https://doi.org/10.1103/PhysRevC.108.045803
J.M. Lattimer, Astrophysics and Cosmology, in Proceedings of the 26th Solvay Conference on Physics, edited by R. Blandford, D. Gross, and A. Sevrin (World Scientific, Singapore, 2014).
P. Bedaque and A.W. Steiner, Phys. Rev. Lett. 114, 031103 (2015); doi: 10.1103/PhysRevLett.114.031103 DOI: https://doi.org/10.1103/PhysRevLett.114.031103
P. Laskos-Patkos, et al., Phys. Rev. C 111, 025801 (2025); doi: 10.1103/PhysRevC.111.025801 DOI: https://doi.org/10.1103/PhysRevC.111.025801
S. Wang, et al., Phys. Rev. C 103, 054319 (2021); doi: 10.1103/PhysRevC.103.054319 DOI: https://doi.org/10.1103/PhysRevD.103.105024
S. Wang, et al., Phys. Rev. C 106, L021305 (2022); doi: 10.1103/PhysRevC.106.L021305 DOI: https://doi.org/10.1103/PhysRevC.106.L021305
H. Tong, et al., Astrophys. J. 930, 137 (2022); doi: 10.3847/1538-4357/ac65fc DOI: https://doi.org/10.3847/1538-4357/ac65fc
S. Wang, et al., Phys. Rev. C 106, 045804 (2022); doi: 10.1103/PhysRevC.106.045804 DOI: https://doi.org/10.1103/PhysRevC.106.045804
X. Qu, et al., Sci. China Phys. Mech. Astron. 66, 242011 (2023); doi: 10.1007/s11433-022-2048-3 DOI: https://doi.org/10.1007/s11433-022-2048-3
P. Qin, et al., Phys. Rev. D 107, 103009 (2023); doi: 10.1103/PhysRevD.107.103009 DOI: https://doi.org/10.1016/j.wsif.2024.103009
D. Farrell and F. Weber, Astrophys. J. 969, 49 (2024); doi: 10.3847/1538-4357/ad47b8 DOI: https://doi.org/10.3847/1538-4357/ad47b8
X. Qu, et al., Astrophys. J. 980, 3 (2025); doi: 10.3847/1538-4357/ada76b DOI: https://doi.org/10.3847/1538-4357/ada76b
Z.F. Seidov, Sov. Astron. 15, 347 (1971). DOI: https://doi.org/10.1080/08838157109363653