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GCN Circular 21527

LIGO/Virgo G298048: Updated sky map from gravitational-wave data
2017-08-17T23:54:40Z (7 years ago)
Reed Clasey Essick at MIT <>
The LIGO Scientific Collaboration and the Virgo Collaboration report:

Parameter estimation has been performed using LALInference (Veitch et
al., PRD 91, 042003) and a revised sky map, preliminary-LALInference.fits.gz, is
available for retrieval from the GraceDB event page:

We caution that this is a preliminary map from the offline parameter 
estimation. This analysis uses data from the LIGO Hanford, LIGO Livingston,
and Virgo detectors with the noise transient in Livingston
removed from the data prior to the analysis, as described in GCN 21513. 
Posterior chains in the parameter estimation may not yet have fully converged.

The 50% and 90% credible regions span about 8.6 and 33.6 square
degrees, respectively, which are somewhat larger than the initial
BAYESTAR sky map. The centroid (maximum a posteriori) sky 
location is R.A.=13h09m, Dec.=-25d37m.

We will continue to refine the sky map as offline parameter estimation
improves and as we apply additional methods of cleaning the data.
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