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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').

17435 results found.

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

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