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arXiv · 1608.07589

An Einstein@home search for continuous gravitational waves from Cassiopeia A

Sylvia J. Zhu·Maria Alessandra Papa·Heinz-Bernd Eggenstein·Reinhard Prix·Karl Wette·Bruce Allen·Oliver Bock·David Keitel·Badri Krishnan·Bernd Machenschalk·Miroslav Shaltev·Xavier Siemens
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Abstract

We report the results of a directed search for continuous gravitational-wave emission in a broad frequency range (between 50 and 1000 Hz) from the central compact object of the supernova remnant Cassiopeia A (Cas A). The data comes from the sixth science run of LIGO and the search is performed on the volunteer distributed computing network Einstein@Home. We find no significant signal candidate, and set the most constraining upper limits to date on the gravitational-wave emission from Cas A, which beat the indirect age-based upper limit across the entire search range. At around 170 Hz (the most sensitive frequency range), we set 90% confidence upper limits on the gravitational wave amplitude $h_0$ of $\sim\!\!~2.9\times 10^{-25}$, roughly twice as constraining as the upper limits from previous searches on Cas A. The upper limits can also be expressed as constraints on the ellipticity of Cas A; with a few reasonable assumptions, we show that at gravitational-wave frequencies greater than 300~Hz, we can exclude an ellipticity of $\gtrsim\!\!~10^{-5}$.

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Sylvia J. Zhu, Maria Alessandra Papa, Heinz-Bernd Eggenstein, Reinhard Prix, Karl Wette, Bruce Allen, Oliver Bock, David Keitel, Badri Krishnan, Bernd Machenschalk, Miroslav Shaltev, Xavier Siemens. 2016-08-26. An Einstein@home search for continuous gravitational waves from Cassiopeia A. https://doi.org/10.1103/physrevd.94.082008

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