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

Introducing the New GCN: Kafka Broker, Circulars Service, and Website

We are pleased to introduce the new General Coordinates Network, the evolution of the Gamma-ray Coordinates Network (now referred to as GCN Classic, this website) 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 and VOEvent delivery methods will continue to be supported for the foreseeable future. However, new features and notice types will only be available on the new web site and GCN Kafka.

Effective April 17, 2023:

The modernized GCN Circulars experience is part of the new GCN web site, where you can

  • Browse and search Circulars in our all-new archive.
  • Sign up for and manage your own email subscriptions.
  • Enroll yourself and your colleagues to submit Circulars with arXiv-style peer endorsements for new contributors.
  • Submit Circulars with our new Web form, or continue to submit by email.

This legacy GCN Classic Circulars service has been disabled.

  • All legacy accounts are transferred to the new system.
  • The legacy archive is frozen.
  • Email submissions to the old address will be forwarded to the new system and processed normally. We encourage use of the new submission address.
For questions, please contact the GCN Team.

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

For questions or subscription changes, please contact the GCN Team.

A service of the HEASARC at the Astrophysics Science Division (ASD) at NASA's GSFC.

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  • Curator: Judith Racusin
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    This file was last modified on Wednesday, 10-Jan-2024 15:26:52 EST