CAOSP abstracts, Volume: 56, No.: 2, year: 2026

Author(s): Huo, J.L.; Wu, X.H.; Ding, W.B.; Zhao, X.F.
Journal: Contributions of the Astronomical Observatory Skalnaté Pleso, vol. 56, no. 2, p. 36-54.
Date: 04/2026
Title: Surface gravitational redshift of massive protoneutron stars: effects of σ^∗ and φ mesons
Keyword(s): stars: binaries, general: stars
Pages: 36 -- 54
DOI: https://doi.org/10.31577/caosp.2026.56.2.36
NASA ADS Abstract Service: 2026CoSka..56b..36H
Citation:
License: This work is licensed under a Creative Commons Attribution 4.0 International License

Abstract: The effects of hyperon interactions (occurring through the coupling of hyperons to the σ^* and ϕ mesons) on the surface gravitational redshift z of proto-neutron stars (PNSs)—specifically PSR J0740+6620, PSR J0348+0432, PSR J1614-2230, and PSR J0737-3039A—are investigated using relativistic mean field theory. It is found that the increase in central pressure and central energy density due to hyperon interactions becomes more pronounced for higher-mass PNSs, while for lower-mass PNSs this effect is negligible. When hyperon interactions are included, the mass M, compactness M/R, and surface gravitational redshift z of a PNS all decrease at a given central energy density ε_c. For the higher-mass PNSs PSR J0740+6620 and PSR J0348+0432, the influence of hyperon interactions on compactness M/R and surface redshift z is significant. In contrast, for the lower-mass PNSs PSR J1614-2230 and PSR J0737-3039A, the effect on M/R and z is negligible.