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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"

23838 results found.

  1. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  2. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  3. BeppoSAX: A new fast X-ray transient
  4. GRB990510: X-ray afterglow
  5. GRB 990510: BATSE Observations
  6. GRB 990506: BATSE Observations
  7. GRB990323 PRECISE IPN POSITION
  8. GRB990316: simultaneous optical observation
  9. GRB990316 - Optical null results
  10. ASM/IPN error box for GRB 990308 (BATSE #7457)
  11. GRB 990308a and GRB 990308b
  12. BATSE Resumes Normal Operations
  13. Search for Potential Images of GRB 990123
  14. Search for Potential Images of GRB 990123
  15. GRB990123, OSSE observations
  16. GRB 990123: Strong MeV CGRO-COMPTEL detection now posted on WWW
  17. GRB 990123: BATSE Observations
  18. GRB990123, early optical counterpart detection
  19. GRB990123, BeppoSAX WFC detection and NFI planned follow-up
  20. Possible identification of SN1999E with GRB980910
  21. GRB 980923 BATSE Observations
  22. GRB980703 - BeppoSAX/GRBM detection
  23. GRB 980703: BATSE Observations
  24. RXTE Observation of GRB 980706
  25. GRB980703: LOTIS observation at early times
  26. GRB 980703: ASM Position & Intensity
  27. GRB 980613: BATSE Observations
  28. SGR1627-41, BeppoSAX-GRBM detections
  29. Discovery of a new SGR source, SGR1627-41
  30. BATSE on-board GRB trigger change
  31. GRB980519 BATSE Observations
  32. BATSE on-board GRB trigger change
  33. GRB980519, BeppoSAX-WFC updated position
  34. GRB980519, BeppoSAX-WFC position
  35. GRB980425 BATSE observations
  36. GRB 971024: Refined analysis by USNOFS Observations
  37. GRB 971024: USNO Observations
  38. GRB 970925: BATSE Localization

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