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GCN: The Gamma-ray Coordinates Network (TAN: Transient Astronomy Network)

Introducing new GCN Kafka broker and web site for transient alerts:

We are pleased to introduce the new General Coordinates Network, the evolution of the Gamma-ray Coordinates Network (now referred to as GCN Classic) using modern, open-source, reliable, and secure alert distribution technologies that have been established by the broader astronomy community and promoted by the Vera C. Rubin Observatory.

GCN has a redesigned website, and a new improved method of streaming GCN Notices called GCN Classic over Kafka, and a self-service configuration of GCN Notices over Email. All three classic GCN Notice formats (text, VOEvent, 160-byte binary packet) are now also available over Kafka or self-service email. This new Kafka streaming service can be used as a drop-in replacement for GCN Classic socket and VOEvent subscribers, and the self-service emails replace GCN Classic Notice subscriptions.

The web site that you are viewing now (the old GCN Classic web site) and the legacy socket delivery methods will continue to be supported for the foreseeable future. However, starting later this year new features and notice types will only be available on the new web site and GCN Kafka.

(This announcement is excerpts from GCN 32419 and GCN 32517.)

The GCN system distributes:
  1. Locations of GRBs and other Transients (the Notices) detected by spacecraft (most in real-time while the burst is still bursting and others are that delayed due to telemetry down-link delays).
  2. Reports of follow-up observations (the Circulars) made by ground-based and space-based optical, radio, X-ray, TeV, and other particle observers.
These two functions provide a one-stop shopping network for follow-up sites and GRB and transient researchers.

The GCN system can be explored using the links above and below.

Invitation to subscribe to the Notices or Circulars here.    unsubscribe here.
Make a modification to an existing Notices site configuration here.
Invitation to producers to incorporate your events into GCN here.

System Status
System Status: Latest update: 17 Mar 2021 (UT)
What's New
What's New: Latest update: 31 Jul 2020 (UT)

thumbnail of GCN physical network
The physical GCN network. (Click to enlarge.)

Latest Gamma-Ray Bursts

GCN Circulars Archive     Circs by Burst
GCN Reports Archive

The GCN/TAN contact is: Scott Barthelmy. For questions or subscription changes, please contact the GCN Team.

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    This file was last modified on Tuesday, 27-Sep-2022 11:38:32 EDT