News Overview

An international team of researchers led by STRUC­TURES member Fabian Schneider predicts that black hole mergers produce chirp sounds in two universal frequency ranges.

They are mysterious, exciting and inescapable – black holes are some of the most exotic objects in the Universe. With gravitational-wave detectors, it is possible to detect the chirp sound that two black holes produce when they merge, approximately 70 such chirps have been found so far. Based on the frequency evolution of this chirp signal, scientists can infer the so-called “chirp mass”, a combination of the two individual black hole masses. So far, it has been assumed that the merging black holes can have any mass. In their new study, published in The Astrophysical Journal Letters, STRUC­TURES Member Fabian Schneider (Hei­del­berg Institute for Theo­re­ti­cal Studies, HITS) and his team, however, predict that in this “ocean of voices”, chirps preferentially occur in two universal frequency ranges. The team's simulations align precisely with observations of the "stellar graveyard" – a collection of all known masses of the neutron-star and black-hole remains of massive stars – which reveal intriguing peaks at approximately 8 and 14 solar masses. With gravitational-wave astronomy paving the way for unprecedented insights into the cosmos, this re­search opens up a new frontier of exploration, helping scientists understand better where the singing black holes in this ocean of voices come from.

• Original Press Release by HITS
• Original Publication: Fabian R. N. Schneider, Philipp Podsiadlowski, and Eva Laplace (2023). The Astrophysical Journal Letters, 950, 2, DOI 10.3847/2041-8213/acd77a
• Stellar Evolution Theory Group at HITS