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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 −25 at 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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Probing more deeply in an all-sky search for continuous gravitational waves in the LIGO O3 data set
We report results from an all-sky search of the LIGO data from the third LIGO-Virgo-KAGRA run (O3) for continuous gravitational waves from isolated neutron stars in the frequency band [30, 150] Hz and spindown range of [−1 × 10−8, +1 × 10−9] Hz/s. This search builds upon a previous analysis of the first half of the O3 data using the same PowerFlux pipeline. We search more deeply here by using the full O3 data and by using loose coherence in the initial stage with fully coherent combination of LIGO Hanford (H1) and LIGO Livingston (L1) data, while limiting the frequency band searched and excluding narrow, highly disturbed spectral bands. We detect no signal and set strict frequentist upper limits on circularly polarized and on linearly polarized wave amplitudes, in addition to estimating population-averaged upper limits. The lowest upper limit obtained for circular polarization is ∼ 4.5 × 10−26, and the lowest linear polarization limit is ∼ 1.3 × 10−25 (both near 144 Hz). The lowest estimated population-averaged upper limit is ∼ 1.0 × 10−25. In the frequency band and spindown range searched here, these limits improve upon the O3a PowerFlux search by a median factor of ∼ 1.4 and upon the best previous limits obtained for the full O3 data by a median factor of ∼ 1.1.
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- Award ID(s):
- 2110181
- PAR ID:
- 10519299
- Publisher / Repository:
- American Physical Society
- Date Published:
- Journal Name:
- Physical Review D
- Volume:
- 109
- Issue:
- 4
- ISSN:
- 2470-0010
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1103/PhysRevD.109.043049
