TITLE:   GCN CIRCULAR
NUMBER:  25504
SUBJECT: SUBJECT: LIGO/Virgo S190828j: Updated Sky Localization
DATE:    19/08/28 08:56:19 GMT
FROM:    Olivier Minazzoli at LIGO Virgo Collaboration  <olivier.minazzoli@ligo.org>

The LIGO Scientific Collaboration and Virgo Collaboration report:

We have updated the skymap for the compact binary merger candidate S190828j
(GCN 25497). The event's properties can be found at this URL:

https://gracedb.ligo.org/superevents/S190828j/

bayestar.fits.gz is the preferred sky map at this time and can be retrieved
from the

GraceDB event page:

 * bayestar.fits.gz, an updated localization generated by BAYESTAR [1],
distributed via GCN update notice about 1.5 hours after the candidate

The 90% credible region is 587 deg2. Marginalized over the whole sky, the a
posteriori luminosity distance estimate is 1803 +/- 423 Mpc (a posteriori
mean +/- standard deviation).

Note that S190828j (GCN 25497) and S190828l (GCN 25503) are distinct events
that occurred 21 minutes apart.

For further information about analysis methodology and the contents of this
alert, refer to the LIGO/Virgo Public Alerts User Guide <
https://emfollow.docs.ligo.org/userguide/>.

 [1] Singer & Price PRD 93, 024013 (2016)