Primordial black holes (PBHs) can constitute the predominant fraction of dark matter (DM) if PBHs reside in the currently unconstrained "sublunar'' mass range. PBHs originating from scalar perturbations generated during inflation can naturally appear with a broad spectrum in a class of models. The resulting stochastic gravitational wave (GW) background generated from such PBH production can account for the recently reported North American Nanohertz Observatory for Gravitational Waves (NANOGrav) pulsar timing array data signal, and will be testable in future GW observations by interferometer-type experiments such as Laser Interferometer Space Antenna (LISA). We show that the broad mass function of such PBH DM is already being probed by Subaru Hyper Suprime-Cam (HSC) microlensing data and is consistent with a detected candidate event. Upcoming observations of HSC will be able to provide an independent definitive test of the stochastic GW signals originating from such PBH DM production scenarios.

中文翻译：

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用光学望远镜测试来自原始黑洞的随机引力波信号

如果原始黑洞 (PBH) 位于当前不受约束的“月下”质量范围内，那么原始黑洞 (PBH) 可以构成暗物质 (DM) 的主要部分。源自膨胀期间产生的标量扰动的 PBH 可以自然地以广谱出现在一类由这种 PBH 产生产生的随机引力波 (GW) 背景可以解释最近报道的北美纳赫兹引力波天文台 (NANOGrav) 脉冲星定时阵列数据信号，并将在未来的 GW 观测中通过干涉仪类型进行测试实验，例如激光干涉仪空间天线（LISA）。我们表明，斯巴鲁 Hyper Suprime-Cam（HSC）微透镜数据已经探测到这种 PBH DM 的宽质量函数，并且与检测到的候选事件一致。即将进行的 HSC 观测将能够对源自此类 PBH DM 生产场景的随机 GW 信号进行独立的确定性测试。