1. On the increase in the concentration of primordial black holes in the halos of dwarf galaxies
- Author
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Pilipenko, S. V., Tkachev, M. V., and Arakelyan, N. R.
- Subjects
Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
Through numerical experiments, we have predicted that if dark matter (DM) contains even a small fraction, $f_0\sim10^{-4}$, of primordial black holes (PBHs), during the formation of the gravitationally bound halo of a dwarf galaxy, these PBHs will concentrate in a region with a radius of about 10 pc, so that their local fraction will exceed 1%. Unlike previous studies of PBH migration to the centers of galaxies, the numerical experiments conducted here take into account the early formation of a massive "dress" of DM around the PBHs and the non-stationarity of the halo during its formation. Applying our results to models of heating stellar clusters in the Eridanus II and Segue I galaxies due to dynamical friction between stars and PBHs allows us to impose constraints on the abundance of PBHs that are two orders of magnitude stricter than previously thought., Comment: 9 pages, 6 figures, accepted in JETPL
- Published
- 2025