2026/03/26 by Adrian Abac, The LIGO Scientific Collaboration, the Virgo Collaboration +1784
Physics and Astronomy · #Amplitude #Astrophysics and Cosmic Phenomena #Cover (algebra) #Gamma-ray bursts and supernovae #Gravitational wave #Neutron star #Pulsar #Pulsars and Gravitational Waves Research #Supernova
paper · pdf · open access · doi:10.3847/1538-4357/ae6263
published in The Astrophysical Journal 1004(2), 204 (IOP Publishing)
openalex publication_date 2026/06/15 · openalex created_date 2026/06/16 · openalex updated_date 2026/08/05
Abstract We present results from directed searches for continuous gravitational waves from a sample of 15 nearby supernova remnants, likely hosting young neutron star candidates, using data from the first eight months of the fourth observing run (O4) of the LIGO–Virgo–KAGRA Collaboration. The analysis employs five pipelines: four semicoherent methods—the Band-Sampled-Data directed pipeline, Weave, and two Viterbi pipelines (single- and dual-harmonic)—and PyStoch, a cross-correlation-based pipeline. These searches cover wide frequency bands and do not assume prior knowledge of the targets’ ephemerides. No evidence of a signal is found from any of the 15 sources. We set 95% confidence-level upper limits on the intrinsic strain amplitude, with the most stringent constraints reaching ∼4 × 10 −26 near 300 Hz for the nearby source G266.2−1.2 (Vela Jr.). We also derive limits on neutron star ellipticity and r -mode amplitudes for the same source, with the best constraints reaching ≲10 −7 and ≲10 −5 , respectively, at frequencies above 400 Hz. For frequencies above 200 Hz, these results represent the most sensitive wide-band directed searches for continuous gravitational waves from supernova remnants to date.