The GCN Team announces updates to LVK and CHIME Notices and a schema release. LVK Notices Exclusively Available in JSON over Kafka As of July 8, 2026, the LIGO-Virgo-KAGRA (LVK) collaboration has ceased sending gravitational wave alerts in the VOEvent format to GCN Classic (https://gcn.gsfc.nasa.gov). The LVK VOEvent alerts were converted to all other GCN Classic formats and distribution methods (text via email and binary via socket connection). As a result, this change also disables all legacy LVK formats (text, binary, VOEvent) distributed over Kafka and email. GCN now distributes LVK Notices exclusively as JSON over Kafka. The LVK Public Alerts User Guide (https://emfollow.docs.ligo.org/userguide/) has been updated to provide information on the alert system that will be deployed in the next observation run (IR1) that is expected to start in late 2026 (https://observing.docs.ligo.org/plan/). To receive GCN Notices on LVK during IR1, please subscribe to JSON-format Notices on the Kafka topic igwn.gwalert (https://gcn.nasa.gov/docs/notices/consuming). At this time, these Notices are only available via Kafka, not email. Updated CHIME Notices CHIME is now distributing retractions of their FRB Notices on the topic gcn.notices.chime.frb, and has updated the example added in Schema v7.2.1 (https://gcn.nasa.gov/docs/schema/stable/gcn/notices/chime/frb.schema.json). Schema v7.2.3 GCN Schema v7.2.3 is available with recent changes including updated Notice examples (Release Notes; https://github.com/nasa-gcn/gcn-schema/releases/tag/v7.2.3). For more details on this new feature and an archive of GCN news and announcements, see https://gcn.nasa.gov/news. For questions, issues, or bug reports, please contact us via: - Contact form: https://gcn.nasa.gov/contact - GitHub issue tracker: https://github.com/nasa-gcn/gcn.nasa.gov/issues --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...