# Results from an Einstein@Home search for continuous gravitational waves from Cassiopeia A, Vela Jr. and G347.3

## TL;DR

This paper presents the most sensitive search to date for continuous gravitational waves from three supernova remnants, using Einstein@Home volunteers' computing power, setting new upper limits on wave amplitudes and ellipticities.

## Contribution

It introduces the most sensitive search for gravitational waves from Cassiopeia A, Vela Jr., and G347.3, improving previous limits by a factor of 2 across 20-1500 Hz.

## Key findings

- No significant gravitational wave signals detected.
- Set the most stringent upper limits on wave amplitudes to date.
- Probed ellipticity values as low as 3×10⁻⁸ for Vela Jr.

## Abstract

We report results of the most sensitive search to date for periodic gravitational waves from Cassiopeia A, Vela Jr. and G347.3 with frequency between 20 and 1500 Hz. The search was made possible by the computing power provided by the volunteers of the Einstein@Home project and improves on previous results by a factor of 2 across the entire frequency range for all targets. We find no significant signal candidate and set the most stringent upper limits to date on the amplitude of gravitational wave signals from the target population, corresponding to sensitivity depths between 54 $[1/ {\sqrt{\textrm{Hz}}}]$ and 83 $[1/ {\sqrt{\textrm{Hz}}}]$, depending on the target and the frequency range. At the frequency of best strain sensitivity, near $172$ Hz, we set 90% confidence upper limits on the gravitational wave intrinsic amplitude of $h_0^{90\%}\approx 10^{-25}$, probing ellipticity values for Vela Jr. as low as $3\times 10^{-8}$, assuming a distance of 200 pc.