Motivated by the unknown nature of the 2.50-2.67M compact object in the binary merger event GW190814, we study the maximum neutron star mass based on constraints from low-energy nuclear physics, neutron star tidal deformabilities from GW170817, and simultaneous mass-radius measurements of PSR J0030+045 from NICER. Our prior distribution is based on a combination of nuclear modeling valid in the vicinity of normal nuclear densities together with the assumption of a maximally stiff equation of state at high densities, a choice that enables us to probe the connection between observed heavy neutron stars and the transition density at which conventional nuclear physics models must break down. We demonstrate that a modification of the highly uncertain suprasaturation density equation of state beyond 2.64 times normal nuclear density is required in order for chiral effective field theory models to be consistent with current neutron star observations and the existence of 2.6M neutron stars. We also show that the existence of very massive neutron stars strongly impacts the radii of ≈2.0M neutron stars (but not necessarily the radii of 1.4M neutron stars), which further motivates future NICER radius measurements of PSR J1614-2230 and PSR J0740+6620.
|Journal||Physical Review C|
|Publication status||Published - 2021 Sept|
Bibliographical noteFunding Information:
Acknowledgments. Y.L. was supported in part by the Max Planck Society and the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation), Project ID 279384907-SFB 1245 and by Ewha Womans University Research Grant of 2021(1-2021-0520-001-1). D.P. and A.B. acknowledge support from NSF DMS (1854731, 1916371) and NSF CCF 1934904 (HDR-TRIPODS). In addition, A.B. acknowledges NSF CAREER 1653404 for supporting this project. The work of J.W.H. is supported by the National Science Foundation under Grant No. PHY1652199 and by the U. S. Department of Energy National Nuclear Security Administration under Grant No. DE-NA0003841. Portions of this research were conducted with the advanced computing resources provided by Texas A&M High Performance Research Computing.
© 2021 American Physical Society.
All Science Journal Classification (ASJC) codes
- Nuclear and High Energy Physics