TITLE:   GCN CIRCULAR
NUMBER:  37597
SUBJECT: LIGO/Virgo/KAGRA S240924a: Updated Sky localization
DATE:    24/09/24 14:27:40 GMT
FROM:    Aaron Zimmerman at U. of Texas at Austin <aaron.zimmerman@utexas.edu>

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

We have conducted further analysis of the LIGO Hanford Observatory (H1), LIGO Livingston Observatory (L1), and Virgo Observatory (V1) data around the time of the compact binary merger (CBC) candidate S240924a (GCN Circular 37592). 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/S240924a

For the Bilby.multiorder.fits,0 sky map, the 90% credible region is 660 deg2. Marginalized over the whole sky, the a posteriori luminosity distance estimate is 3816 +/- 1285 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/.

 [1] Ashton et al. ApJS 241, 27 (2019) doi:10.3847/1538-4365/ab06fc and Morisaki et al. PRD 108, 123040 (2023) doi:10.1103/PhysRevD.108.123040