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Abstract 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 LIGO data below 125 Hz and 8.7 days of LIGO data above 125 Hz from the second Advanced LIGO–Virgo observing run. We found no astrophysical signal. We set upper limits on GW emission as tight as an intrinsic strain of 2 × 10−25at 90% confidence. The large spin-down parameter space makes this search the first astrophysically consistent one for continuous GWs from NS 1987A. Our upper limits are the first consistent ones to beat an analog of the spin-down limit based on the age of the neutron star and hence are the first GW observations to put new constraints on NS 1987A.
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Improved Upper Limits on Gravitational-wave Emission from NS 1987A in SNR 1987A
Abstract We report on a new search for continuous gravitational waves from NS 1987A, the neutron star born in SN 1987A, using open data from Advanced LIGO and Virgo’s third observing run (O3). The search covered frequencies from 35–1050 Hz, more than 5 times the band of the only previous gravitational-wave search to constrain NS 1987A. Our search used an improved code and coherently integrated from 5.10 to 14.85 days depending on frequency. No astrophysical signals were detected. By expanding the frequency range and using O3 data, this search improved on strain upper limits from the previous search and was sensitive at the highest frequencies to ellipticities of 1.6 × 10−5andr-mode amplitudes of 4.4 × 10−4, both an order of magnitude improvement over the previous search and both well within the range of theoretical predictions.
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- PAR ID:
- 10490677
- Publisher / Repository:
- DOI PREFIX: 10.3847
- Date Published:
- Journal Name:
- The Astrophysical Journal Letters
- Volume:
- 962
- Issue:
- 2
- ISSN:
- 2041-8205
- Format(s):
- Medium: X Size: Article No. L23
- Size(s):
- Article No. L23
- Sponsoring Org:
- National Science Foundation
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