Motivated by the unknown nature of the $2.50\text{–}2.67M_{\odot }$ 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 $2.6M_{\odot }$ neutron stars. We also show that the existence of very massive neutron stars strongly impacts the radii of $\approx 2.0M_{\odot }$ neutron stars (but not necessarily the radii of $1.4M_{\odot }$ neutron stars), which further motivates future NICER radius measurements of PSR $\mathrm{J1614}-2230$ and PSR J0740+6620.

中文翻译：

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来自大质量中子星和 GW190814 的半径和状态方程约束

受到未知性质的启发 $2.50\text{——}2.67{米}_{\odot }$作为双星合并事件 GW190814 中的致密天体，我们基于来自低能核物理的约束、来自 GW170817 的中子星潮汐变形能力以及来自 NICER 的 PSR J0030+045 的同步质量半径测量来研究最大中子星质量。我们的先验分布基于在正常核密度附近有效的核建模与高密度下最大刚性状态方程的假设相结合，这种选择使我们能够探测观测到的重中子星与常规核物理模型必须分解的跃迁密度。我们证明了对超过 2 的高度不确定的超饱和状态密度方程的修改。$2.6{米}_{\odot }$中子星。我们还表明，非常大质量的中子星的存在强烈影响$\approx 2.0{米}_{\odot }$ 中子星（但不一定是 $1.4{米}_{\odot }$ 中子星），这进一步激发了未来 PSR 的 NICER 半径测量 $\mathrm{J1614}-2230$ 和 PSR J0740+6620。