TITLE: GCN CIRCULAR NUMBER: 27951 SUBJECT: LIGO/Virgo MS200615h: Retraction of a test binary neutron star candidate DATE: 20/06/15 16:21:57 GMT FROM: Ryan Magee at LVC 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 locations are fictitious. *** We identified the compact binary merger candidate MS200615h during real-time processing of data from LIGO Hanford Observatory (H1) and LIGO Livingston Observatory (L1) at 2020-06-15 00:35:41.894 UTC (GPS time: 1276216559.894). The candidate was found by the GstLAL [1] analysis Pipeline in the early warning configuration, and an Early Warning GCN Notice was issued. The GCN Notice included the standard data products associated with CBC alerts, namely localization [2] and source classification [3]. However, this Early Warning alert (MS200615h) is no longer of interest because it was not detected by the regular, full-bandwidth search. [1] Messick et al. PRD 95, 042001 (2017) [2] Singer & Price PRD 93, 024013 (2016) [3] Chatterjee et al. The Astrophysical Journal 896, 1 (2020)