Search of the Early O3 LIGO Data for Continuous Gravitational Waves from the Cassiopeia A and Vela Jr. Supernova Remnants

TL;DR

This study conducted directed searches for continuous gravitational waves from neutron stars in the Cassiopeia A and Vela Jr. supernova remnants using LIGO data, achieving the most sensitive results to date but detecting no signals.

Contribution

First application of the Weave semi-coherent method to search for continuous gravitational waves from these supernova remnants in LIGO data, setting new sensitivity limits.

Findings

No gravitational wave signals detected.

Achieved strain sensitivity as low as ~$6.3 imes10^{-26}$ for Cas A.

Set new upper limits on gravitational wave emission.

Abstract

We present directed searches for continuous gravitational waves from the neutron stars in the Cassiopeia A (Cas A) and Vela Jr. supernova remnants. We carry out the searches in the LIGO data from the first six months of the third Advanced LIGO and Virgo observing run, using the Weave semi-coherent method, which sums matched-filter detection-statistic values over many time segments spanning the observation period. No gravitational wave signal is detected in the search band of 20--976 Hz for assumed source ages greater than 300 years for Cas A and greater than 700 years for Vela Jr. Estimates from simulated continuous wave signals indicate we achieve the most sensitive results to date across the explored parameter space volume, probing to strain magnitudes as low as ~$6.3\times10^{-26}$ for Cas A and ~$5.6\times10^{-26}$ for Vela Jr. at frequencies near 166 Hz at 95% efficiency.