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General Coordinates Network

GCN Circulars are now administered through the General Coordinates Network (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.

About the GCN/TAN

A Brief Description
There are two parts to the GRB Coordinates Network (GCN) (TAN: Transient Astronomy Network):
(1) the real-time (and near real-time) distribution of GRB locations, images, spectra, & lightcurves, (in < 2sec inside GCN) detected by various spacecraft (Swift, Fermi, MAXI, INTEGRAL, IPN, etc), and
(2) the distribution of follow-up observation reports submitted by the GRB/transient community.
INVITATION to Join/Subscribe (Notices & Circulars)
An open invitation for GRB researchers and institutions to join GCN/TAN. For people wishing to receive the GCN/TAN Notices, the required pieces of information to set up an entry in the "sites.cfg" file are listed.
And for those individuals wanting to receive/submit GCN Circulars, those requirements are also listed.
Scientific Motivation and General Background Information on GRBs
The history and the importance of research into the nature of Gamma-Ray Bursts.
GCN/TAN Sites and Links
The current observing sites participating in the GCN/TAN system are listed. Links are provided when available.
Who we are
The people that built and run the GCN/TAN system.
What's new    (22 Nov 19)
Brief descriptions of new capabilities and operational changes within the GCN/TAN system.

Technical Details

A Full Description of the GCN/TAN System:
The Basic System Description,
The Various Sources of GRB/transient Locations,
Distribution Methods,
Coordinates Accuracy,
Improvements Made to the System,
Future Improvements to the System,
Detailed Technical Descriptions and Specifications,
Related Services and Activities,
Real-time Aspects of these Webpages.

Mission-Instrument Notices at-a-Glance

Clicking the links will take you to the Description/Documentation pages
and to the tables of archived past Notices.
Description Notice
Description Notice
IPN   CGRO n/a
KONUS table BeppoSAX table
INTEGRAL GRBs table NEAR table
Swift GRBs table HETE table
Swift GND_ANALYSIS table MILAGRO table
Swift BAT SubSubThresh table XTE-PCA,   -ASM table
Swift BAT Monitor table Suzaku table
AGILE GRBs table    
AGILE MCAL table    
Fermi GRBs table    
Fermi GBM Subthresh table    
Fermi LAT Monitor&Trans table    
MAXI table    
MOA table    
SNEWS table    
SK_SN table    
CALET table    
AMON Gold&Bronze tableAMON EHE table
AMON NU_EM table    
AMON CASCADE table    
LIGO/Virgo table    
GECAM table    
SIMBAD-NED n/a    

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

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    This file was last modified on Monday, 17-Apr-2023 13:39:27 EDT