Directed searches for broadband extended gravitational-wave emission in nearby energetic core-collapse supernovae

Understand

Core-collapse supernovae are factories of neutron stars and stellar mass black holes.

• Type Ib/c supernovae stand out as potentially originating in relatively compact stellar binaries and their branching ratio of about 1\% into long gamma-ray bursts.
• The most energetic events probably derive from central engines harboring rapidly rotating black holes, wherein accretion of fall-back matter down to the Inner Most Stable Circular Orbit (ISCO) offers a window to {\em broadband extended gravitational-wave emission} (BEGE).
• To search for BEGE, we introduce a butterfly filter in time-frequency space by Time Sliced Matched Filtering.