Searches for continuous gravitational waves from young supernova remnants in the early third observing run of Advanced LIGO and Virgo

TL;DR

This study conducted three wide-band searches for continuous gravitational waves from 15 young supernova remnants using Advanced LIGO and Virgo data, setting upper limits and constraining neutron star properties without detecting signals.

Contribution

It presents the first wide-band directed searches for continuous gravitational waves from these remnants, employing multiple pipelines and establishing new upper limits on signal strain and neutron star parameters.

Findings

No evidence of continuous gravitational waves was found.

Set upper limits on signal strain at 95% confidence, reaching as low as 7.7×10⁻²⁶.

Constrained neutron star ellipticity and r-mode amplitude to below 10⁻⁷ and 10⁻⁵, respectively.

Abstract

We present results of three wide-band directed searches for continuous gravitational waves from 15 young supernova remnants in the first half of the third Advanced LIGO and Virgo observing run. We use three search pipelines with distinct signal models and methods of identifying noise artifacts. Without ephemerides of these sources, the searches are conducted over a frequency band spanning from 10~Hz to 2~kHz. We find no evidence of continuous gravitational radiation from these sources. We set upper limits on the intrinsic signal strain at 95\% confidence level in sample sub-bands, estimate the sensitivity in the full band, and derive the corresponding constraints on the fiducial neutron star ellipticity and $r$-mode amplitude. The best 95\% confidence constraints placed on the signal strain are $7.7\times 10^{-26}$ and $7.8\times 10^{-26}$ near 200~Hz for the supernova remnants G39.2--0.3 and G65.7+1.2, respectively. The most stringent constraints on the ellipticity and $r$-mode amplitude reach $\lesssim 10^{-7}$ and $ \lesssim 10^{-5}$, respectively, at frequencies above $\sim 400$~Hz for the closest supernova remnant G266.2--1.2/Vela Jr.