Multimessenger Cocoons in Dying Stars: New LIGO-Detectable Gravitational Wave Sources

Upcoming LIGO/Virgo/KAGRA (LVK) observing runs promise to detect a variety of inspiralling gravitational wave (GW) sources. With powerful phenomena such as gamma-ray bursts and supernovae unable to produce detectable GW signals in LVK, all non-inspiral GW sources remain firmly out of reach for the next decade. Using state-of-the-art simulations that for the first time, follow jets from a newly formed black hole (BH) in a collapsing star to outside the star, I will present the first class of non-inspiral GW sources, that is powerful and abundant enough such that its detection by LVK can be imminent. The BH-powered jets wobble inside the star and inflate an energetic bubble - cocoon, which inevitably develop turbulence with a broad power spectrum that translates into broadband, powerful quasi-isotropic GW emission within the LVK band. The GW emission is well within our observational grasp as the estimated detection rate is 0.1--3 events in LVK runs O3/O4. With a detection horizon of ~100 Mpc, these GWs are expected to be accompanied by detectable energetic core-collapse supernova and cocoon electromagnetic emission, making jetted stellar explosions promising multi-messenger sources, enabling targeted searches for GWs based on the electromagnetic counterpart detection.