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arXiv · 2208.01683

Ruling out Initially Clustered Primordial Black Holes as Dark Matter

V. De Luca·G. Franciolini·A. Riotto·H. Veermäe
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Abstract

Combining constraints from microlensing and Lyman-$\alpha$ forest, we provide a simple argument to show that large spatial clustering of stellar-mass primordial black holes at the time of formation, such as the one induced by the presence of large non-Gaussianities, is ruled out. Therefore, it is not possible to evade existing constraints preventing stellar-mass primordial black holes to be a dominant constituent of the dark matter by boosting their initial clustering.

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V. De Luca, G. Franciolini, A. Riotto, H. Veermäe. 2022-08-02. Ruling out Initially Clustered Primordial Black Holes as Dark Matter. https://doi.org/10.1103/physrevlett.129.191302

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