Early structure formation in primordial black hole cosmologies
Early structure formation in primordial black hole cosmologies
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DOI：
10.1103/physrevd.100.083528
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发表时间：
2019-07
影响因子：
5
通讯作者：
Derek Inman;Yacine Ali-Haïmoud
中科院分区：
文献类型：
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作者：
Derek Inman;Yacine Ali-Haïmoud
冷暗物质（CDM）可能由原始黑洞（PBH）组成，或者取代更正统的弱相互作用大质量粒子暗物质（PDM）。我们研究了这种λ PBH宇宙学中第一个结构的形成，使用了从辐射时代深处到红移99的N -体模拟。当PBH仅是CDM的一小部分时，它们被PDM包裹以形成孤立的光晕。另一方面，当PBH产生大部分CDM时，光晕也可以通过许多PBH聚集而产生。我们发现在随机初始条件下，用泊松统计量可以很好地模拟光晕质量函数。我们量化了由结构形成引起的非线性速度，发现它们太小而不能显著影响CMB约束。一个主要的挑战是如何最好地推断我们的结果，以降低与某些观测限制相关的红移。
Cold dark matter (CDM) could be composed of primordial black holes (PBH) in addition to or instead of more orthodox weakly interacting massive particle dark matter (PDM). We study the formation of the first structures in such $\Lambda$PBH cosmologies using $N$-body simulations evolved from deep in the radiation era to redshift 99. When PBH are only a small component of the CDM, they are clothed by PDM to form isolated halos. On the other hand, when PBH make most of the CDM, halos can also grow via clustering of many PBH. We find that the halo mass function is well modelled via Poisson statistics assuming random initial conditions. We quantify the nonlinear velocities induced by structure formation and find that they are too small to significantly impact CMB constraints. A chief challenge is how best to extrapolate our results to lower redshifts relevant for some observational constraints.