Search for continuous gravitational waves from neutron stars in globular cluster NGC 6544

Author(s)

Powell, J.

Abstract

We describe a directed search for continuous gravitational waves in data from the sixth initial LIGO science run. The target was the nearby globular cluster NGC 6544 at a distance of ≈2.7  kpc. The search covered a broad band of frequencies along with first and second frequency derivatives for a fixed sky position. The search coherently integrated data from the two LIGO interferometers over a time span of 9.2 days using the matched-filtering F-statistic. We found no gravitational-wave signals and set 95% confidence upper limits as stringent as 6.0×10−25 on intrinsic strain and 8.5×10−6 on fiducial ellipticity. These values beat the indirect limits from energy conservation for stars with characteristic spin-down ages older than 300 years and are within the range of theoretical predictions for possible neutron-star ellipticities. An important feature of this search was use of a barycentric resampling algorithm which substantially reduced computational cost; this method is used extensively in searches of Advanced LIGO and Virgo detector data.

Publication year

2017

Publication type

Journal article

Source

Physical Review D, Vol. 95 (Apr 2017), article no. 082005

ISSN

2470-0029

Publisher

American Physical Society

Copyright

Copyright © 2017 American Physical Society.

Additional information

Many more authors listed at Publisher’s URL

Details