We consider some properties and possible observational manifestations of the very heavy primordial black holes (PBHs), with masses ∼ (109 − 1010)M ⊙. These black holes should be surrounded by the dense dark matter and baryonic halos even at early cosmological epochs. There are mechanisms as for radiation emission in the centers due to accretion and for deep absorption of relic radiation at the periphery of the halos. We calculate the absorption profile in the 21cm line of atomic hydrogen by solving the equations of radiation transfer through the baryonic halo around a PBH. The calculations show that a spherical absorbing layer appears around the object, which can be observed with radio telescopes. Also, at some epochs, shock waves may form at the periphery of the objects. The accelerated charged particles can radiate in radio frequency band, so it is possible that these objects can explain the recently discovered radio circles.

中文翻译：

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高红移的超大质量原始黑洞

我们考虑了非常重的原始黑洞 (PBH) 的一些特性和可能的​​观测表现，具有质量 ～ (109 - 1010)米 ⊙. 即使在早期的宇宙学时代，这些黑洞也应该被密集的暗物质和重子晕包围。由于吸积导致中心的辐射发射和晕圈外围的遗迹辐射的深度吸收存在机制。我们计算 21 中的吸收曲线通过求解通过 PBH 周围的重子晕的辐射传输方程，得到原子氢的 cm 线。计算表明，物体周围出现了一个球形吸​​收层，可以用射电望远镜观察到。此外，在某些时期，冲击波可能会在物体的外围形成。加速后的带电粒子可以在无线电频带内辐射，因此这些物体有可能解释最近发现的射电圈。