First search for gravitational waves from the youngest known neutron star

Document #:

LIGO-P1000028-v7

Document type:

P - Publications

Abstract:

We present a search for periodic gravitational waves from the neutron star in the supernova remnant Cassiopeia A. The search coherently analyzes data in a 12-day interval taken from the fifth science run of the Laser Interferometer Gravitational-Wave Observatory. It searches gravitational wave frequencies from 100 to 300~Hz, and covers a wide range of first and second frequency derivatives appropriate for the age of the remnant and for different spin-down mechanisms. No gravitational wave signal was detected. Within the range of search frequencies, we set 95\% confidence upper limits of \( 0.7 \)--\( 1.2 \times 10^{-24} \) on the intrinsic gravitational wave strain, \( 0.4 \)--\( 4 \times 10^{-4} \) on the equatorial ellipticity of the neutron star, and \( 0.005 \)--\( 0.14 \) on the amplitude of \( r \)-mode oscillations of the neutron star. These direct upper limits beat indirect limits derived from energy conservation and enter the range of theoretical predictions involving crystalline exotic matter or runaway \( r \)-modes. This paper is also the first gravitational-wave search to present upper limits on the \( r \)-mode amplitude.

Files in Document:

• AASTeX format (CasAResultsPaperAAS.pdf, 492.3 kB)
• ApJ format (CasAResultsPaperApJ.pdf, 517.2 kB)

Topics:

• Continuous Wave

Author Groups:

• LSC

Notes and Changes:

Some small changes in response to the referee, and minor proof corrections. Accepted for publication in ApJ.

Journal References:

Published in ApJ vol. 722 pg. 1504.