5–9 Jul 2026
University of Canterbury
Pacific/Auckland timezone

PBH Flybys of SMBHs: Say Hello, Wave Goodbye

8 Jul 2026, 13:50
20m
Room E5 (Rātā / Engineering Core Building, University of Canterbury)

Room E5

Rātā / Engineering Core Building, University of Canterbury

63 Creyke Road, Ilam, Christchurch 8041, New Zealand
Parallel Session Talk Parallel sessions

Speaker

Laura Burn (University of Auckland)

Description

Primordial black holes (PBHs), assumed to form in the early Universe, remain a viable dark matter candidate. Since dark matter is expected to be concentrated toward galactic centres, a significant population of PBHs would reside near a supermassive black hole (SMBH), creating a promising environment for gravitational wave emission. We consider a population of PBHs with masses in the range $10^{-15} - 10 \, \mathrm{M_{\odot}}$ on hyperbolic trajectories near a SMBH, producing bursts of gravitational radiation during periastron passage. We focus on Sagittarius A* due to its proximity, and also consider M87*, with results that generalise to other scenarios. We compute the density of PBHs required to give rise to a popcorn gravitational wave background within the sensitivity range of future space-based detectors, including LISA and the proposed next generation $\mu$Ares detector.

Research Area Gravitational waves: black holes

Author

Laura Burn (University of Auckland)

Co-authors

Nelson Christensen (Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Artemis) Richard Easther (The University of Auckland)

Presentation materials