All-sky search for long-duration gravitational-wave transients in the second Advanced LIGO observing run

Understand

We present the results of a search for long-duration gravitational-wave transients in the data from the Advanced LIGO second observation run; we search for gravitational-wave transients of $2~\text{--}~ 500$~s duration in the $24 - 2048$\,Hz frequency band with minimal assumptions about signal properties such as waveform morphologies, polarization, sky location or time of occurrence.

• Targeted signal models include fallback accretion onto neutron stars, broadband chirps from innermost stable circular orbit waves around rotating black holes, eccentric inspiral-merger-ringdown compact binary coalescence waveforms, and other models.
• The second observation run totals about \otwoduration~days of coincident data between November 2016 and August 2017.
• We find no significant events within the parameter space that we searched, apart from the already-reported binary neutron star merger GW170817.