TITLE: GCN CIRCULAR NUMBER: 34366 SUBJECT: LIGO/Virgo/KAGRA S230808i: Identification of a GW unmodeled transient candidate DATE: 23/08/08 05:18:56 GMT FROM: Shivaraj Kandhasamy at Inter-University Centre for Astronomy and Astrophysics (LVK collaboration) The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration report: We identified the unmodeled transient candidate S230808i during real- time processing of data from LIGO Hanford Observatory (H1) and LIGO Livingston Observatory (L1) at 2023-08-08 04:03:46.430 UTC (GPS time: 1375502644.430). The candidate was found by the CWB [1] analysis pipeline. S230808i is an event of interest because its false alarm rate, as estimated by the online analysis, is 6.9e-11 Hz, or about one in 1e3 years. The event's properties can be found at this URL: https://gracedb.ligo.org/superevents/S230808i Two sky maps are available at this time and can be retrieved from the GraceDB event page: * cwb.multiorder.fits,0, an initial localization generated by cWB [1], distributed via GCN notice about 2 minutes after the candidate event time. * cwb.multiorder.fits,1, an initial localization generated by cWB [1], distributed via GCN notice about 7 minutes after the candidate event time. The preferred sky map at this time is cwb.multiorder.fits,1. For the cwb.multiorder.fits,1 sky map, the 90% credible region is 7195 deg2. 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] Klimenko et al. PRD 93, 042004 (2016)