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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

3925 results found.

  1. GRB030329: multiple re-brightening phases
  2. GRB: Non-Referencing of GCN Circulars.
  3. GRB030115: Optical Observations, Swiss Telescope at La Silla (ESO, Chile)
  4. Distribution of INTEGRAL SPI-ACS triggers for GRB bursts
  5. Distribution of INTEGRAL SPI-ACS triggers
  6. GRB021016(=H2397): A Long GRB Localized by HETE
  7. GRB 021004: Optical observations, AUDE network
  8. IPN GCN Circulars now to be issued without restriction
  9. GRB/XRF 020427, detection of an underlying system with the VLT
  10. HETE Fully-Automated GCN Notices
  11. Congratulate Scott on the 1000th GRB Coordinates Network Circular!
  12. HETE Status
  13. HETE positions added to GCN
  14. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  15. GRB000301c results
  16. Optical observations of GRB000301c
  17. GCN resumes full operations
  18. X-ray/GRB 1SAX J0835.9+5118, Optical Observations
  19. BeppoSAX: A new fast X-ray transient
  20. GRB 990506, Optical Observations
  21. GRB 990123: near-infrared observations.
  22. GRB981226, BeppoSAX Christmas GRB
  23. GRB980515, BeppoSAX IAUC to be submitted
  24. IPN web site of GRBs
  25. GRB980329, Fading IR counterpart to radio source

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Download all Circulars as a .tar.gz archive:
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