Comparison of methods for the detection of gravitational waves from unknown neutron stars
Rapidly rotating neutron stars are promising sources of continuous gravitational wave radiation for the LIGO and Virgo interferometers. The majority of neutron stars in our galaxy have not been identified with electromagnetic observations. All-sky searches for isolated neutron stars offer the potential to detect gravitational waves from these unidentified sources. The parameter space of these blind all-sky searches, which also cover a large range of frequencies and frequency derivatives, presents a significant computational challenge. Different methods have been designed to perform these searches within acceptable computational limits. Here we describe the first benchmark in a project to compare the search methods currently available for the detection of unknown isolated neutron stars. The five methods compared here are individually referred to as the PowerFlux, sky Hough, frequency Hough, Einstein@Home, and time domain F-statistic methods. We employ a mock data challenge to compare the ability of each search method to recover signals simulated assuming a standard signal model. We find similar performance among the four quick-look search methods, while the more computationally intensive search method, Einstein@Home, achieves up to a factor of two higher sensitivity. We find that the absence of a second derivative frequency in the search parameter space does not degrade search sensitivity for signals with physically plausible second derivative frequencies. We also report on the parameter estimation accuracy of each search method, and the stability of the sensitivity in frequency and frequency derivative and in the presence of detector noise.
© 2016 Published by the American Physical Society. Published by the American Physical Society under the terms of the Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI. Received 3 June 2016; published 8 December 2016. The authors would like to thank Erin Macdonald for starting the setup of the MDC, and the LIGO and Virgo CW group for useful insights and discussions. The authors gratefully acknowledge support from the following grants. The Einstein@Home and PowerFlux teams acknowledge the National Science Foundation Grants No. NSF PHY 1104902 and No. NSF PHY 1505932, respectively. The Einstein@Home team also acknowledges the support of the Max-Planck-Society, and the computing resources of the ATLAS super-computing cluster at the Max-Planck-Institut für Gravitationsphysik/Leibniz Universität Hannover. The time domain F -statistic is supported by the National Science Centre of Poland Grant No. UMO-2014/14/M/ST9/00707 and in part by the PL-Grid infrastructure. Sky Hough is supported by the Spanish Ministerio de Economía y Competitividad (Grants No. FPA2013-41042-P, No. CSD2009-00064, No. FPA2015-69815-REDT, No. FPA2015-68783-REDT, and No. FPA2016-76821-P); the Conselleria d'Innovació, Recerca i Turisme del Govern de les Illes Balears, and the European Union FEDER funds. M. P. is funded by the Science and Technology Facilities Council under Grant No. ST/L000946/1. The authors gratefully acknowledge the Italian Istituto Nazionale di Fisica Nucleare. This paper was assigned LIGO document number P1600128.
Submitted - 1606.00660v2.pdf
Published - PhysRevD.94.124010.pdf