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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"

19141 results found.

  1. Mars Odyssey joins the IPN
  2. IPN detection and localization of Cygnus X-1 flares
  3. RXTE Observations of SGR 1900+14
  4. SGR1900+14 activity
  5. IPN/HETE Detection of Bursts from SGR1900+14
  6. IPN detection of further activity from SGR1806-20
  7. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  8. Probable SGR or Short Duration GRB Detected by HETE
  9. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  10. Possible burst from SGR1806-20
  11. IPN detection of SGR1900+14
  12. X-ray precursors to the large flare from SGR 1900+14
  13. SGR 1900+14: No evidence of extended X-ray emission
  14. SGR 1900+14 : RXTE observations
  15. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  16. SGR1900+14
  17. SGR 1900+14: Correction to GCN 1049
  18. Millimeter observation of SGR 1900+14
  19. SGR 1900+14: Detection of extended X-ray emission
  20. Chandra Observations of SGR 1900+14
  21. SGR 1900+14, Chandra observations
  22. Chandra Observations of SGR 1900+14
  23. SGR1900+14, I-band observations
  24. SGR 1806-20 burst activity
  25. BATSE GRB trigger criteria
  26. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  27. GRB990308 not a new SGR
  28. GRB990308, Possible new SGR~0209+70
  29. SGR1900+14, BeppoSAX-GRBM observations
  30. SGR1627-41
  31. SGR1627-41, RXTE/ASM observations
  32. Reduced error box of SGR 1627-41
  33. SGR 1627-41
  34. Discovery of a new SGR source, SGR1627-41
  35. SGR 1900+14
  36. SGR1900+14
  37. SGR1900+14
  38. BATSE on-board GRB trigger change
  39. IRAS 18119-1342 and the possible new SGR
  40. Possible new SGR from US Naval Observatory
  41. RXTE Observations of SGR 1814-13

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