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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"

3735 results found.

  1. GRB 020321: Candidate X-ray Counterparts
  2. GRB011212: Optical Observations
  3. GRB020127(=H1902): Localization of a Double-Peaked GRB by HETE
  4. GRB011212: Optical observations at Gunma
  5. GRB011130 (=XRF011130): Further analysis of Chandra Target of
  6. IPN triangulation of GRB011121
  7. GRB 010629 Optical Observations
  8. GRB 010222
  9. IPN/RXTE TRIANGULATION OF GRB010126
  10. GRB010126, TNG R-band observations
  11. GRB010126 optical observations
  12. IPN TRIANGULATION OF GRB010126
  13. IPN triangulation of GRB001219
  14. IPN triangulation of GRB000911
  15. IPN localization of GRB000820
  16. IPN localization of GRB000811
  17. GRB000607, A SHORT, HARD BURST
  18. GRB000424, optical observations
  19. IPN localization of GRB991226
  20. GRB 991106, LOTIS Optical Observations
  21. IPN/NFI error box for GRB991014
  22. IPN error box for GRB990915 (=BATSE 7766)
  23. GRB990806 UBVRIJHK observations
  24. GRB990704, optical observations
  25. IPN error box for GRB990527
  26. IPN localization for GRB990506
  27. GRB 990316, Optical observations
  28. GRB990308, Possible new SGR~0209+70
  29. GRB990123, early optical counterpart detection
  30. GRB 981226 Optical Observations
  31. GRB 981226 optical observations
  32. GRB980326 IPN annulus
  33. Near-IR follow-up on GRB 971227
  34. Optical Observations of the GRB 971227 field
  35. GRB971227: Further CAHA R-band images

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Download all Circulars as a .tar.gz archive:
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