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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

15 results found.

  1. GRB 250704A: GRANDMA observations
  2. GRB 250704A: SVOM/ECLAIRs refined analysis
  3. GRB 250704B / EP250704a: 1.3 GHz MeerKAT Detection
  4. IPN triangulation of GRB 250704B (short/hard, consistent with EP 250704a)
  5. GRB 250704B / EP250704a: VLA radio detection
  6. GRB 250704A: SVOM/COLIBRÍ (FM-GFT) optical observations
  7. GRB 250704A: Swift/BAT-GUANO localization skymap of a burst
  8. GRB 250704A: Swift/UVOT Detection
  9. GRB 250704A: SVOM/VT optical observation
  10. EP 250704a: BOOTES-5 optical detection
  11. GRB 250704A: VLT/X-shooter afterglow discovery and spectroscopic redshift z = 1.091
  12. GRB 250704A: Swift-XRT afterglow detection
  13. GRB 250704A: REM retraction of optical afterglow detection and updated limit
  14. GRB 250704A: REM detection of the optical afterglow
  15. GRB 250704A: SVOM detection of a burst

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
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