Parameter Estimation on Gravitational Waves from Neutron-star Binaries with Spinning Components
Inspiraling binary neutron stars (BNSs) are expected to be one of the most significant sources of gravitational-wave signals for the new generation of advanced ground-based detectors. We investigate how well we could hope to measure properties of these binaries using the Advanced LIGO detectors, which began operation in September 2015. We study an astrophysically motivated population of sources (binary components with masses 1.2 M⊙-1.6 M⊙ and spins of less than 0.05) using the full LIGO analysis pipeline. While this simulated population covers the observed range of potential BNS sources, we do not exclude the possibility of sources with parameters outside these ranges; given the existing uncertainty in distributions of mass and spin, it is critical that analyses account for the full range of possible mass and spin configurations. We find that conservative prior assumptions on neutron-star mass and spin lead to average fractional uncertainties in component masses of ~16%, with little constraint on spins (the median 90% upper limit on the spin of the more massive component is ~0.7). Stronger prior constraints on neutron-star spins can further constrain mass estimates but only marginally. However, we find that the sky position and luminosity distance for these sources are not influenced by the inclusion of spin; therefore, if LIGO detects a low-spin population of BNS sources, less computationally expensive results calculated neglecting spin will be sufficient for guiding electromagnetic follow-up.
© 2016 The American Astronomical Society. Received 2015 August 21; revised 2016 March 9; accepted 2016 March 10; published 2016 July 11. The authors are grateful for useful suggestions from the CBC group of the LIGO Scientific–Virgo Collaboration. In particular, we are grateful to Walter Del Pozzo for useful advice, Vivien Raymond for helpful discussions, Simon Stevenson for careful reading, and Neil Cornish for beneficial comments. B.F. was supported by the Enrico Fermi Institute at the University of Chicago as a McCormick Fellow. This work was supported in part by the Science and Technology Facilities Council. P.B.G. acknowledges NASA grant NNX12AN10G. S.V. acknowledges the support of the National Science Foundation and the LIGO Laboratory. J.V. was supported by STFC grant ST/K005014/1. LIGO was constructed by the California Institute of Technology and Massachusetts Institute of Technology with funding from the National Science Foundation and operates under cooperative agreement PHY-0757058. This work used computing resources at CIERA funded by NSF PHY-1126812, as well as the computing facilities of the LIGO Data Grid including: the Nemo computing cluster at the Center for Gravitation and Cosmology at the University of Wisconsin–Milwaukee under NSF Grants PHY-0923409 and PHY-0600953; the Atlas computing cluster at the Albert Einstein Institute, Hannover; the LIGO computing clusters at Caltech, and the facilities of the Advanced Research Computing @ Cardiff (ARCCA) Cluster at Cardiff University. Some results were produced using the post-processing tools of the plotutils library at http://github.com/farr/plotutils and skyarea library at https://github.com/farr/skyarea. This paper has been assigned LIGO document reference LIGO-P1500117.
Published - apj_825_2_116.pdf
Submitted - 1508.05336v3.pdf