论文标题
GW190425，GW190521和GW190814：QCD时期的原始黑洞的三个候选合并
GW190425, GW190521 and GW190814: Three candidate mergers of primordial black holes from the QCD epoch
论文作者
论文摘要
在第三次观察Ligo/处女座的第三次观测中，最近的两个重力波事件GW190425和GW190814都具有同伴，如果起源于中子星或恒星黑洞，则具有质量$ [1.6-2.5] 〜M_ \ m_ \ odot $和$ [2.5-2.7] 〜M_ $ $ $ $ $ \ odot $ [1.6-2.5] 460^{+1050}_{-360} $ and $ 7^{+16}_{-6}$ events/yr/Gpc$^3$ respectively, at 90\% c.l.. Moreover, the recent event GW190521 has black hole components with masses 67 and $91~M_\odot$, and therefore lies in the so-called pair-instability mass间隙，不应直接形成恒星黑洞。所有这些紧凑的物体都是原始黑洞（PBH）的可能性。宇宙的已知热历史预测，PBH形成在QCD过渡时会增强，在此特定的质量尺度上引起了它们的分布峰值，并且在$ 30-50〜M_ \ odot $上升起。我们发现，从GW190425，GW190521和GW190814推断出的合并率与在物质时代或早期宇宙中密集的光环中捕获形成的PBH二进制文件一致。同时，黑洞合并的速率约为$ 30〜m_ \ odot $和亚壁PBH合并的速度不超过Ligo/处女座限制。这样的PBH可以解释很大的一部分，甚至可以解释深色物质的整体，但是必须充分地聚集它们才能与当前的天体物理限制保持一致。
The two recent gravitational-wave events GW190425 and GW190814 from the third observing run of LIGO/Virgo have both a companion which is unexpected if originated from a neutron star or a stellar black hole, with masses $[1.6-2.5]~M_\odot$ and $[2.5-2.7]~M_\odot$ and merging rates $ 460^{+1050}_{-360} $ and $ 7^{+16}_{-6}$ events/yr/Gpc$^3$ respectively, at 90\% c.l.. Moreover, the recent event GW190521 has black hole components with masses 67 and $91~M_\odot$, and therefore lies in the so-called pair-instability mass gap, where there should not be direct formation of stellar black holes. The possibility that all of these compact objects are Primordial Black Holes (PBHs) is investigated. The known thermal history of the Universe predicts that PBH formation is boosted at the time of the QCD transition, inducing a peak in their distribution at this particular mass scale, and a bump around $30-50~M_\odot$. We find that the merging rates inferred from GW190425, GW190521 and GW190814 are consistent with PBH binaries formed by capture in dense halos in the matter era or in the early universe. At the same time, the rate of black hole mergers around $30~M_\odot$ and of sub-solar PBH mergers do not exceed the LIGO/Virgo limits. Such PBHs could explain a significant fraction, or even the totality of the Dark Matter, but they must be sufficiently strongly clustered in order to be consistent with current astrophysical limits.
