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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"

19531 results found.

  1. GRB 071003 Optical observations
  2. GRB 071003: KAIT optical afterglow observations
  3. GRB 071003: Swift detection of a bright burst
  4. GRB 070714B: host galaxy spectroscopic redshift
  5. GRB 071001: Swift-XRT Team refined analysis
  6. GRB 071001, Swift-BAT refined analysis
  7. Faulkes Telescope South observations of GRB 071001
  8. GRB 071001: Swift detection of a burst
  9. VLA observation of GRB 070923
  10. Disregard the Swift-XRT Notices today
  11. GRB070925: Swift-XRT Afterglow confirmation
  12. GRB070925: Swift-XRT Position
  13. Update on Swift Status
  14. GRB 070920B: ROTSE-III Early Optical Limits
  15. Recent SGR1806-20 Activity
  16. GRB 070923, Swift-BAT refined analysis
  17. GRB 070920B: XRT observations
  18. GRB 070923: Swift detection of a short hard burst
  19. GRB 070917: Suzaku/WAM observation of the prompt emission
  20. GRB 070920B: TAROT La Silla observatory optical observations
  21. GRB 070917: Confirmation of the X-ray afterglow
  22. GRB 070920B, Swift-BAT refined analysis
  23. GRB 070911: Swift/BAT and Suzaku/WAM joint spectral analysis
  24. GRB 070920B: NOT optical observations
  25. GRB 070920B: Swift detection of a burst
  26. GRB 070920, Swift-BAT refined analysis
  27. GRB 070920: TAROT Calern observatory optical observations
  28. GRB 070920: Swift detection of a burst
  29. SGR1806-20: Swift-BAT detection of enhanced activity
  30. GRB 070917: pseudo-z= 2.40 from prompt emission spectrum
  31. Konus-Wind observation of GRB 070917
  32. Swift Status and XRT Calibration Uncertainties
  33. GRB 070917: Swift-XRT observations
  34. GRB 070917: KAIT optical limits
  35. GRB 070917: R band observations
  36. GRB 070917, Swift-BAT refined analysis
  37. GRB 070917: Swift detection of a bright burst
  38. GRB 070911: Suzaku WAM observation of the prompt emission
  39. GRB 070913: Swift-XRT detection of the possible X-ray afterglow
  40. GRB 070809: The Swift evidence for the SHB nature of this burst
  41. GRB 070913: Swift-BAT refined analysis
  42. GRB 070913: Corrected BAT position
  43. GRB 070913: TAROT La Silla observatory optical observations
  44. GRB 070913: Swift detection of a burst
  45. Swift-BAT Notices back to autonomous real-time distribution
  46. GRB 070911: Swift XRT refined analysis
  47. GRB 070911, Swift-BAT refined analysis
  48. GRB 070911: Swift detection of a burst
  49. IPN search for a GRB associated with TAROT transient on August 31
  50. Intense burst from SGR 1806-20 detected on September 7
  51. GRB 070824 - Combined SuperAGILE/IPN Localization
  52. GRB 070731: Swift/UVOT Upper Limit
  53. GRB 070805: UVOT afterglow candidate retraction
  54. GRB070810b: optical candidate
  55. GRB 070810A: ROTSE-III Refined Analysis
  56. Swift observatory off line
  57. GRB070810B: Swift/UVOT Upper Limits
  58. GRB 070810B: XRT refined analysis
  59. GRB 070810B, Swift-BAT refined analysis
  60. GRB 070809: Swift/UVOT Corrected Photometry
  61. Swift Alert 070810.8: MASTER optical observation
  62. Swift Trigger 287421: False trigger due to star tracker loss
  63. GRB 070810A: Swift-BAT refined analysis
  64. GRB 070809: Swift/UVOT Upper Limits
  65. GRB 070810B: Swift detection of a short burst
  66. VLA upper limit on the short hard burst GRB 070729
  67. No radio detection in superAGILE burst 070724B
  68. GRB 070810: Swift-XRT Team Refined Analysis
  69. GRB 070809: Swift-XRT refined analysis
  70. GRB 070810: enhanced Swift-XRT position
  71. GRB 070810: Swift/UVOT Optical Counterpart
  72. GRB 070810: ROTSE-III Detection of Optical Counterpart
  73. GRB 070810: Swift detection of a burst
  74. GRB 070809, Swift-BAT refined analysis
  75. GRB 070808: Swift/UVOT upper limits
  76. GRB 070809: ROTSE-III Optical Limits
  77. GRB 070809: Swift detection of a short burst
  78. GCN Swift XRT update position notices and enhanced position circulars
  79. GRB 070808: Swift XRT refined analysis
  80. GRB 070808, Swift-BAT refined analysis
  81. GRB070808 - SDSS Pre-Burst Observations
  82. GRB 070808: ROTSE-III Optical Limits
  83. GRB 070808: Swift detection of a burst
  84. GRB070805 XRT and UVOT afterglow candidate
  85. Swift trigger on 4U 1700-377 while star tracker loss-of-lock
  86. Swift/UVOT observations of GRB070805
  87. GRB 070805, Swift-BAT refined analysis
  88. GRB 070805: Swift XRT initial analysis.
  89. GRB 070805: Swift/UVOT initial analysis
  90. GRB 070805: Swift detection of a burst
  91. UVOT observations of SAXJ1810.8-2609
  92. Swift detection of a outburst from SAX J1810.8-2609
  93. VLA non-detection of GRB 070721B
  94. GRB 070802: REM optical observations
  95. GRB 070724B: Swift-XRT afterglow confirmation
  96. GRB 070802: Swift-XRT refined analysis
  97. GRB070802: Swift/UVOT upper limits
  98. GRB 070802, Swift-BAT refined analysis
  99. GRB 070802: refined Swift XRT position
  100. GRB 070802: GROND J band candidate

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