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GCN Circular 26734

LIGO/Virgo S200114f: Identification of a GW unmodeled transient candidate
2020-01-14T03:24:22Z (4 years ago)
Deep Chatterjee at University of Wisconsin, Milwaukee <>
The LIGO Scientific Collaboration and the Virgo Collaboration report:

We identified the unmodeled transient candidate S200114f during real-
time processing of data from LIGO Hanford Observatory (H1), LIGO
Livingston Observatory (L1), and Virgo Observatory (V1) at 2020-01-14
02:08:18.239 UTC (GPS time: 1263002916.239). The candidate was found
by the CWB [1] analysis pipeline with a version of the search called
�IMBH�. This name is not a classification of the candidate.

S200114f is an event of interest because its false alarm rate, as
estimated by the online analysis, is 1.2e-09 Hz, or about one in 25
years. The event's properties can be found at this URL:

Two sky maps are available at this time and can be retrieved from the
GraceDB event page:
 * cWB.fits.gz,1, an initial localization generated by cWB,
distributed via GCN notice about 5 minutes after the candidate event
 * cWB.fits.gz,3 -- this is identical to cWB.fits.gz,1

The preferred sky map at this time is cWB.fits.gz,3. For the
cWB.fits.gz,3 sky map, the 90% credible region is 403 deg2.

For further information about analysis methodology and the contents of
this alert, refer to the LIGO/Virgo Public Alerts User Guide

 [1] Klimenko et al. PRD 93, 042004 (2016)
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