Kilohertz quasiperiodic oscillations in short gamma-ray bursts.

Short gamma-ray bursts (GRBs) are associated with binary neutron star mergers, which are multimessenger astronomical events that have been observed both in gravitational waves and in the multiband electromagnetic spectrum. Depending on the masses of the stars in the binary and on details of their largely unknown equation of state, a dynamically evolving and short-lived neutron star may be formed after the merger, existing for approximately 10-300 ms before collapsing to a black hole. Numerical relativity simulations across different groups consistently show broad power spectral features in the 1-5-kHz range in the post-merger gravitational-wave signal, which is inaccessible by current gravitational-wave detectors but could be seen by future third-generation ground-based detectors in the next decade.