论文标题
探索紧凑型二进制进化中较低的质量差距和不平等的质量状态
Exploring the Lower Mass Gap and Unequal Mass Regime in Compact Binary Evolution
论文作者
论文摘要
2019年8月14日，Ligo和处女座探测器观察到GW190814，这是一个引力波信号，源自合并$ \ simeq 23 m_ \ odot $ black hole，带有$ \ simeq 2.6 m_ \ odot $ compact对象。 GW190814的紧凑型二进制源在其高度不对称的质量中是非典型的，并且在其低质量成分中，位于最重的已知中子星和紧凑型二进制中最轻的黑洞之间。如果通过孤立的二元进化形成，则次级的质量表示其出生时的质量。我们通过一系列假设构成了封装在大规模二元进化中的许多物理不确定性的假设中，通过隔离的二元进化来研究这种系统的形成。我们更新了在原型压缩物体崩溃期间如何实现中子化过程的质量损失，以消除中子恒星和黑洞之间过渡时质谱中的人造间隙。我们发现，对于种群建模的挑战是与GW190814样系统的经验率相匹配，而同时与引力波观测推断出的其他紧凑型二元种群的速率一致。 Nonetheless, the formation of GW190814-like systems at any measurable rate requires a supernova engine model that acts on longer timescales such that the proto-compact object can undergo substantial accretion immediately prior to explosion, hinting that if GW190814 is the result of massive-star binary evolution, the mass gap between neutron stars and black holes may be narrower or nonexistent.
On August 14, 2019, the LIGO and Virgo detectors observed GW190814, a gravitational-wave signal originating from the merger of a $\simeq 23 M_\odot$ black hole with a $\simeq 2.6 M_\odot$ compact object. GW190814's compact-binary source is atypical both in its highly asymmetric masses and in its lower-mass component lying between the heaviest known neutron star and lightest known black hole in a compact-object binary. If formed through isolated binary evolution, the mass of the secondary is indicative of its mass at birth. We examine the formation of such systems through isolated binary evolution across a suite of assumptions encapsulating many physical uncertainties in massive-star binary evolution. We update how mass loss is implemented for the neutronization process during the collapse of the proto-compact object to eliminate artificial gaps in the mass spectrum at the transition between neutron stars and black holes. We find it challenging for population modeling to match the empirical rate of GW190814-like systems whilst simultaneously being consistent with the rates of other compact binary populations inferred by gravitational-wave observations. Nonetheless, the formation of GW190814-like systems at any measurable rate requires a supernova engine model that acts on longer timescales such that the proto-compact object can undergo substantial accretion immediately prior to explosion, hinting that if GW190814 is the result of massive-star binary evolution, the mass gap between neutron stars and black holes may be narrower or nonexistent.
