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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"

19 results found.

  1. GRB 250924A: SVOM/GRM observation
  2. GRB 250924A: Swift-BAT refined analysis
  3. GRB 250924A: 1.6m Mephisto optical upper limits
  4. GRB 250924A: SAO RAS optical observations
  5. GRB 250924A: NOT optical observations
  6. GRB 250924A: AstroSat CZTI detection
  7. GRB 250924A: SVOM/VT optical observation
  8. GRB 250924A: Swift/UVOT Detection
  9. GRB 250924A: Swift-XRT refined Analysis
  10. GRB 250924A: Enhanced Swift-XRT position
  11. GRB 250924A: J-band detection with WINTER
  12. GRB 250924A: GROWTH-India Telescope Upper Limits
  13. GRB 250924A: KAIT optical observations
  14. GRB 250924A: Mondy optical observations, afterglow fading
  15. GRB 250924A: Kilonova-Catcher optical afterglow detection
  16. GRB 250924A: COLIBRÍ optical observations
  17. Swift GRB 250924A: Global MASTER-Net observations report
  18. GRB 250924A: DDOTI Detection of the Optical Counterpart
  19. GRB 250924A: Swift detection of a burst with an optical counterpart

Advanced

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