Gravitational-wave constraints on the pair-instability mass gap and nuclear burning in massive stars
Michela Mapelli
Nature Astronomy, Published online: 07 May 2026; doi:10.1038/s41550-026-02847-0 Gravitational-wave data reveal evidence for the pair-instability mass gap and a population of high-mass black hole mergers formed in star clusters. The measurement also constrains the nuclear reaction that regulates carbon–oxygen production in massive stars.