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arXiv · 2009.04439

Gravitational-wave Merger Forecasting: Scenarios for the early detection and localization of compact-binary mergers with ground based observatories

Abstract

We present the prospects for the early (pre-merger) detection and localization of compact-binary coalescences using gravitational waves over the next 10 years. Early warning can enable the direct observation of the prompt and early electromagnetic emission of a neutron star merger. We examine the capabilities of the ground based detectors at their "Design" sensitivity (2021-2022), the planned "A+" upgrade (2024-2026), and the envisioned "Voyager" concept (late 2020's). We find that for a fiducial rate of binary neutron star mergers of $1000 ~\mathrm{Gpc}^{-3} \mathrm{yr}^{-1}$, the Design, A+, and Voyager era networks can provide 18, 54, and 195s of warning for one source per year of observing, respectively, with a sky localization area $<$100 deg$^2$ at a $90\%$ credible level. At the same rate, the A+ and Voyager era networks will be able to provide 9 and 43s of warning, respectively, for a source with $<$10 deg$^2$ localization area. We compare the idealized search sensitivity to that achieved by the PyCBC Live search tuned for pre-merger detection. The gravitational-wave community will be prepared to produce pre-merger alerts. Our results motivate the operation of observatories with wide fields-of-view, automation, and the capability for fast slewing to observe simultaneously with the gravitational-wave network.

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BibTeXRIS

Alexander H. Nitz, Marlin Schäfer, Tito Dal Canton. 2020-10-19. Gravitational-wave Merger Forecasting: Scenarios for the early detection and localization of compact-binary mergers with ground based observatories. https://doi.org/10.3847/2041-8213%2Fabbc10

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