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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').

42 results found.

  1. GRB 230510A: Swift detection of a burst
  2. GRB 220427A: Swift detection of a burst with an optical counterpart
  3. Swift trigger 1073821: detection of IGR J16418-4532
  4. Fermi GRB 200604A: Global MASTER-Net observations report
  5. Swift Trigger 863053 is not an astrophysical event
  6. Swift detects a flare from AX 1631.9-4752
  7. Swift Trigger 847216: misidentification of IGR J16385-2057
  8. Swift trigger 773082 is probably not astrophysical
  9. Swift Trigger 727422 is not an astrophysical event.
  10. Swift 650221/IGR J00291+5934: Liverpool Telescope observations
  11. IGR J00291+5934, Swift-BAT refined analysis
  12. Swift Trigger 650221 / IGR J00291+5934: MASTER-IAC OT observations
  13. Trigger 650221: Swift detection of a IGR J00291+5934
  14. Swift IGR J00291+5934: MASTER Optical flare detection
  15. IGR J00291+5934: Swift-BAT refined analysis
  16. Trigger 650140: Swift detection of IGR J00291+5934
  17. Trigger 614903: Swift detection of IGR J17544-2619
  18. Swift Trigger 609694 is probably not an astrophysical source
  19. Swift detection of SFXT IGR J17544-2619
  20. Trigger 599041: Swift detection of SFXT IGR J16479-4514
  21. Swift trigger 559221 is likely a false trigger coincident with IGR J17544-2619
  22. Swift detection of IGR J18245-2452
  23. Swift Trigger 530441 is a false trigger
  24. Swift-BAT trigger 529813 is due to noise while entering the SAA
  25. Watcher follow-up observations of IGR J17062-6143 (Swift trigger 525148)
  26. Skynet/PROMPT observations of IGR J17062-6143 (Swift trigger 525148)
  27. Swift detection of IGR J17062-6143
  28. Swift Trigger 522245 is a noise fluctuation near IGR J17091-3624
  29. Swift detection of 4U 1630-47
  30. Swift-BAT refined analysis of SFXT IGR J08408-4503 (trigger 501368)
  31. Swift-BAT trigger 431582 likely is IGR J17464-2811
  32. Swift detection of outburst from the SFXT IGR J18410-0535
  33. Trigger 371210: Swift/BAT Triggered on IGR J17511-3057
  34. Trigger 324561: IGR J08408-4503 detected by Swift
  35. Refined analysis of Swift Trigger 316063, is IGR J08408-4503
  36. Trigger 316063: Swift detection of a transient
  37. IBAS Alert n. 5257 : not a GRB
  38. Swift-BAT trigger 306829 is IGR J16479-4514
  39. IGR J08408-4503 (= V* LM Vel): Swift detection of a transient
  40. Swift detection of IGR J17497-2821 (trigger 230504)
  41. Swift Trigger #152652 is not a GRB
  42. 030331 NOT A GRB

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