GCN Circular 39143
Subject
LIGO/Virgo/KAGRA S250204ax: Updated Sky localization
Date
2025-02-04T17:06:49Z (6 days ago)
From
Will Farr <will.farr@stonybrook.edu>
Via
Web form
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 S250204ax (GCN Circular 39137). 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/S250204ax
For the Bilby.multiorder.fits,0 sky map, the 90% credible region is 318 deg2. Marginalized over the whole sky, the a posteriori luminosity distance estimate is 2056 +/- 690 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. (2023) arXiv:2307.13380