We calculate the neutrino luminosity when dark matter is captured by a neutron star that eventually implodes to form a low-mass black hole. A central disk forms out of the ejected material with a finite radial extension, density, temperature, and lepton fraction, producing fainter neutrino luminosities and colder associated spectra than expected in regular core-collapse supernova and black hole–neutron star mergers. The emitted gravitational wave signal from the implosion should be detectable with ultrahigh-frequency resonant cavities in the range $\sim 0.1–1\mathrm{GHz}$.

• Received 17 April 2023
• Revised 4 November 2023
• Accepted 24 February 2024

DOI:https://doi.org/10.1103/PhysRevD.109.063015