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arXiv · 2103.16369

Constraining the Initial Primordial Black Hole Clustering with CMB-distortion

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

The merger rate of primordial black holes depends on their initial clustering. In the absence of primordial non-Gaussianity correlating short and large-scales, primordial black holes are distributed \`a la Poisson at the time of their formation. However, primordial non-Gaussianity of the local-type may correlate primordial black holes on large-scales. We show that future experiments looking for CMB $\mu$-distortion would test the hypothesis of initial primordial black hole clustering induced by local non-Gaussianity, while existing limits already show that significant non-Gaussianity is necessary to induce primordial black hole clustering.

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V. De Luca, G. Franciolini, A. Riotto. 2021-03-30. Constraining the Initial Primordial Black Hole Clustering with CMB-distortion. https://doi.org/10.1103/physrevd.104.063526

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