First Constraining Upper Limits on Gravitational Wave Emission from NS 1987A in SNR 1987A

Understand

We report on a search for continuous gravitational waves (GWs) from NS 1987A, the neutron star born in SN 1987A.

• The search covered a frequency band of 75-275 Hz, included a wide range of spin-down parameters for the first time, and coherently integrated 12.8 days of data below 125 Hz and 8.7 days of data above 125 Hz from the second Advanced LIGO observing run.
• We found no astrophysical signal.
• We set upper limits on GW emission as tight as an intrinsic strain of $2\times10^{-25}$ at 90\% confidence.