Unexpected correlations in outstanding subpopulations of the gravitational wave transient catalogue data

TL;DR

This study analyzes gravitational wave data from the third observing run, revealing unexpected linear correlations in certain subpopulations that challenge stochastic explanations and suggest potential new physics or instrumental effects.

Contribution

It identifies and characterizes unexpected linear relations in gravitational wave subpopulations, providing new insights into their properties and potential origins.

Findings

Linear relations in total binary and chirp mass parameters.

Correlations supported by at least five independent events.

Potential implications for understanding specific low-mass events.

Abstract

With the third observing run the number of gravitational wave emitting events has increased significantly. The data of the recorded events is inspected to search for overall properties on the population. The properties of subpopulations are determined and compared to predictions from simulations. It appears that the most outstanding systems follow linear relations in the parameter space of the total binary and the chirp mass. Those relations are too tight to have a stochastic origin and are supported by at least five independent events each. The origin of the correlations is still open to be confirmed, while possible sources, ranging from instrumental artefacts to unknown physics, are discussed and partly excluded. Depending on the relation's source the two events (GW190814 and GW200210_092254) having a smaller mass component between 2.5 and 2.9 Msun may reveal in a very different light.