Speaker
Description
Core-collapse supernovae (CC-SNe) mark the end of the life of massive stars, leaving behind a compact remnant. EM observations alone cannot resolve the astronomical conundrum of identifying the nature of CC-SNe remnant and central engine: neutron star (NS) or black hole (BH). This resolution may come through the radically new window of gravitational wave observation. Conventionally, the horizon distance of LIGO to CC-SNe is believed to be about a few Mpc. Here, a horizon distance of ~160Mpc is demonstrated for CC-SNe powered by rotating BHs, based on their ample energy reservoir described by the Kerr metric. Crucially, this shows these observation can break the degeneracy between NS and BH central engines by GW calorimetry, by a positive observation of one or a confident null detection of the other. Applied to the recent event SN2023ixf, at 6.7Mpc, by the confident null detection of a BH central engine, we identify it to be a NS, whereby the progenitor mass is below $20M_\odot$. [Based on Maurice H. P. M. van Putten, Maryam A. Abchouyeh, Massimo Della Valle, 2024 ApJL 972 L23].