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GCN Circular 25614

LIGO/Virgo S190901ap: Updated Sky Localization
2019-09-02T12:05:35Z (5 years ago)
Peter Shawhan at U of Maryland/LSC <>
The LIGO Scientific Collaboration and the Virgo Collaboration report:

We have conducted further analysis of the LIGO Livingston Observatory
(L1) and Virgo Observatory (V1) data around the time of the compact
binary merger (CBC) candidate S190901ap (GCN Circular
25606). Parameter estimation has been performed using LALInference [1]
and a new sky map, LALInference.v2.fits.gz, distributed via GCN
Notice, is available for retrieval from the GraceDB event page:

The preferred sky map at this time is LALInference.v2.fits.gz. For the
LALInference.v2.fits.gz sky map, the 90% credible region is 14753
deg2. Marginalized over the whole sky, the a posteriori luminosity
distance estimate is 241 +/- 79 Mpc (a posteriori mean +/- standard

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

[1] Veitch et al. PRD 91, 042003 (2015)
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