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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"
  1. GRB 971214: Redshift from Keck Optical Observations
  2. GRB 971214: Apache Point Observatory Optical Observations
  3. GRB 971214: KPNO Optical Observations
  4. Optical Observations of GRB 971214 at Keck
  5. GRB 971214: Optical Observations
  6. Radio Observations of GRB 971214 at the VLA
  7. GRB 971214: USNOFS Observations Summary
  8. GRB 971024: KPNO Optical Observations Summary
  9. GRB 971024: Refined analysis by USNOFS Observations
  10. GRB 971024: KPNO Optical Observations
  11. GRB 971024: USNO Observations
  12. GRB 970925: BATSE Localization
  13. IRAS 18119-1342 and the possible new SGR
  14. Possible new SGR from US Naval Observatory
  15. RXTE Observations of SGR 1814-13
  16. GRB 970828: Palomar Observations
  17. GRB 970228: Keck/LRIS Optical Observations

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Download all Circulars as a .tar.gz archive:
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