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arXiv · 1801.02674

Improvements in Gravitational-Wave Sky Localization with Expanded Networks of Interferometers

Chris Pankow·Eve A. Chase·Scott Coughlin·Michael Zevin·Vassiliki Kalogera
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Abstract

A milestone of multi-messenger astronomy has been achieved with the detection of gravitational waves from a binary neutron star merger accompanied by observations of several associated electromagnetic counterparts. Joint observations can reveal details of the engines that drive the electromagnetic and gravitational-wave emission. However, locating and identify an electromagnetic counterparts to a gravitational-wave event is heavily reliant on localization of the source through gravitational-wave information. We explore the sky localization of a simulated set of neutron star mergers as the worldwide network of gravitational-wave detectors evolves through the next decade, performing the first such study for neutron star -- black hole binary sources. Currently, three detectors are observing with additional detectors in Japan and India expected to become operational in the coming years. With three detectors, we recover a median neutron star -- black hole binary sky localization of 60 deg$^2$ at the 90\% credible level. As all five detectors become operational, sources can be localized to a median of 11 deg$^2$ on the sky.

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Chris Pankow, Eve A. Chase, Scott Coughlin, Michael Zevin, Vassiliki Kalogera. 2018-02-02. Improvements in Gravitational-Wave Sky Localization with Expanded Networks of Interferometers. https://doi.org/10.3847/2041-8213%2Faaacd4

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