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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"

22 results found.

  1. GRB 100206A: optical observations in CrAO
  2. GRB 100206A: optical observations in Terskol
  3. GRB 100206A: Second epoch Gemini-north observations and afterglow limits
  4. GRB 100206A: GROND upper limits
  5. GRB 100206A: Gemini-North observations
  6. GRB 100206A: Swift/UVOT Upper Limits
  7. GRB 100206A: YNAO-GMG observations
  8. GRB 100206A: MASTER-Net optical alert observations
  9. GRB 100206A: PAIRITEL Photometry of Host Candidate
  10. GRB 100206A - Keck/LRIS Spectroscopy
  11. GRB100206: MITSuME optical upper limits
  12. GRB 100206A: NOT NIR observations
  13. GRB 100206A: WHT candidate afterglow
  14. GRB 100206A, RIMOTS optical upper limits
  15. GRB 100206A: optical observations from Southern Spain
  16. GRB 100206A: Swift-XRT refined analysis
  17. GRB 100206A: Fermi GBM observation
  18. GRB 100206A: Optical limit
  19. GRB 100206A: Swift-BAT refined analysis
  20. GRB 100206A: Enhanced Swift-XRT position
  21. GRB 100206A: Pre-explosion imaging and host candidate
  22. GRB 100206A: Swift detection of a short hard burst

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