Impact of dark matter spikes on the merger rates of Primordial Black Holes

Understand

Mergers of Primordial Black Holes (PBHs) may contribute to the gravitational wave mergers detected by the LIGO-Virgo-KAGRA (LVK) Collaboration.

• We study the dynamics of PBH binaries dressed with dark matter (DM) spikes, for PBHs with extended mass functions.
• We analyze the impact of DM spikes on the orbital parameters of the PBH binaries formed in the early Universe and calculate their merger rates at the age of the Universe today.
• We consider two possible scenarios for the dynamics of the dressed binaries: assuming that either the DM spikes are completely evaporated from the binaries before merger or they remain static until the merger.