TITLE:   GCN CIRCULAR
NUMBER:  33883
SUBJECT: LIGO/Virgo/KAGRA S230520ae: Updated Sky localization
DATE:    23/05/26 22:04:48 GMT
FROM:    Deep Chatterjee at MIT <deep.chatterjee@ligo.org>

The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration report:

We have conducted further analysis of the LIGO Hanford Observatory (H1) and LIGO Livingston Observatory (L1) data around the time of the compact binary merger (CBC) candidate S230520ae (GCN Circular 33838). Parameter estimation has been performed using Bilby [1] and a new sky map, Bilby.multiorder.fits,0, distributed via GCN Notice, is available for retrieval from the GraceDB event page:

https://gracedb.ligo.org/superevents/S230520ae

For the Bilby.multiorder.fits,0 sky map, the 90% credible region is 1702 deg2. Marginalized over the whole sky, the a posteriori luminosity distance estimate is 2014 +/- 663 Mpc (a posteriori mean +/- standard deviation).

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

 [1] Ashton et al. ApJS 241, 27 (2019)