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GCN Circular 27989

LIGO/Virgo MS200619bf: Retraction of a test binary neutron star candidate
2020-06-19T13:10:29Z (4 years ago)
Manoj Kovalam at U. of Western Australia <>
The LIGO Scientific Collaboration and the Virgo
Collaboration report:

*** This is a test of the Early Warning alert system
resulting from archival O3 data. Times and sky
localizations are fictitious. ***

We identified the compact binary merger candidate
MS200619bf during real-time processing of data from LIGO
Hanford Observatory (H1) and LIGO Livingston Observatory
(L1) at 2020-06-19 10:25:22.98 UTC (GPS time:
1276597540.98). The candidate was found by the SPIIR
[1] analysis pipeline in the early warning configuration. An Early Warning GCN Notice was issued 28 seconds before the projected merger time. The GCN
Notice included the standard data products associated
with CBC alerts, namely localization [2] and source
classification [3].

However, this Early Warning alert (MS200619bf) is no
longer of interest because it was not detected by the
regular, full-bandwidth search.

[1] Qi Chu, PhD Thesis, The University of Western Australia (2017)
[2] Singer & Price PRD 93, 024013 (2016)
[3] Chatterjee et al. The Astrophysical Journal 896, 1 (2020)
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