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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').

48 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. Swift GRB 210820A: 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 639199: Swift detection of IGRJ16418-4532
  18. Trigger 614903: Swift detection of IGR J17544-2619
  19. Swift Trigger 609694 is probably not an astrophysical source
  20. Swift detection of SFXT IGR J17544-2619
  21. Trigger 599041: Swift detection of SFXT IGR J16479-4514
  22. Swift trigger 559221 is likely a false trigger coincident with IGR J17544-2619
  23. Swift detection of IGR J18245-2452
  24. Swift Trigger 530441 is a false trigger
  25. Swift-BAT trigger 529813 is due to noise while entering the SAA
  26. Watcher follow-up observations of IGR J17062-6143 (Swift trigger 525148)
  27. Skynet/PROMPT observations of IGR J17062-6143 (Swift trigger 525148)
  28. Swift detection of IGR J17062-6143
  29. Swift Trigger 522245 is a noise fluctuation near IGR J17091-3624
  30. Swift detection of 4U 1630-47
  31. Swift-BAT refined analysis of SFXT IGR J08408-4503 (trigger 501368)
  32. Swift-BAT trigger 431582 likely is IGR J17464-2811
  33. Swift detection of outburst from the SFXT IGR J18410-0535
  34. Trigger 371210: Swift/BAT Triggered on IGR J17511-3057
  35. Trigger 324561: IGR J08408-4503 detected by Swift
  36. GRB 080810: Swift/UVOT Refined Analysis
  37. Refined analysis of Swift Trigger 316063, is IGR J08408-4503
  38. Trigger 316063: Swift detection of a transient
  39. IBAS Alert n. 5257 : not a GRB
  40. Swift-BAT trigger 306829 is IGR J16479-4514
  41. IGR J08408-4503 (= V* LM Vel): Swift detection of a transient
  42. Swift detection of IGR J17497-2821 (trigger 230504)
  43. GRB 060116: Further analysis of VLT photometry and optical spectroscopy
  44. GRB 060116: photometric redshift - the farthest GRB?
  45. GRB 060116: possible I-J dropout
  46. GRB 060116: UKIRT IR Observations
  47. Swift Trigger #152652 is not a GRB
  48. 030331 NOT A GRB

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