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.