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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

18486 results found.

  1. GRB 090915: GROND upper limits
  2. GRB 090915: SARA detection of afterglow candidate
  3. GRB 090912: optical observation
  4. GRB 090915: Swift/UVOT detection of an optical afterglow candidate
  5. GRB 090915: Swift-XRT detection of a fading X-ray counterpart
  6. GRB 090915 Swift-BAT detection of a burst in ground analysis
  7. GRB 090827: Confirmation of the X-ray afterglow
  8. GRB 090912: Swift/UVOT Upper Limits
  9. GRB 090912 optical upper limit
  10. GRB 090912: Enhanced Swift-XRT position
  11. GRB 090912: Swift detection of a burst
  12. GRB 090814A: Skynet/DSO & GORT Observations
  13. GRB 090823: Swift XRT confirmation of the X-ray afterglow
  14. GRB 090904B: GROND detection of the optical afterglow
  15. GRB 090904B: Swift/UVOT Refined Analysis
  16. GRB 090902B: VLA radio detection
  17. GRB 090904B: Enhanced Swift-XRT position
  18. GRB 090904A: Enhanced Swift-XRT position
  19. GRB 090904A: NOT observations
  20. GRB090904B: REM observations
  21. GRB 090904B: Swift detection of a burst
  22. GRB 090904: Swift detection of a burst
  23. GRB 090902B: Swift/UVOT refined analysis
  24. GRB 090902B: GROND NIR Afterglow Observations
  25. GRB 090902B: Enhanced Swift-XRT position
  26. GRB090902B: Swift/UVOT observations
  27. GRB 090902B: Swift/XRT Afterglow Candidate
  28. GRB 090902B: Fermi LAT detection
  29. GRB 090831C: GROND upper limits
  30. Konus-Wind observations of GRB 090831A
  31. Swift Trigger 361477, called GRB090831B, is probably not real.
  32. GRB090831C: Swift/UVOT upper limits
  33. GRB 090831B: MITSuME optical upper limits
  34. GRB 090829B: Fermi GBM Detection
  35. GRB 090831C: Enhanced Swift-XRT position
  36. GRB 090831C: Swift detection of a burst
  37. GRB 090831B, RIMOTS optical upper limits
  38. GRB 090831B: Swift detection of a possible burst
  39. Konus-Wind observations of GRB 090827
  40. GRB 090827: Swift XRT and UVOT observations
  41. GRB 090817 - TLS Observations
  42. GRB 090823: Swift XRT possible detection of the X-ray afterglow
  43. GRB 090817: Swift/UVOT Observations of a Host Galaxy Candidate
  44. GRB 090820: MASTER-Net optical polarization observations
  45. GRB 090817: optical upper limit
  46. GRB 090817: Confirmation of the X-ray afterglow
  47. GRB 090817: Swift/UVOT Upper Limits
  48. GRB 090817: Swift-XRT observations
  49. GRB 090814A: optical observations
  50. VLA radio non-detection of GRB 090812
  51. GRB 090813: CrAO optical obsevations
  52. GRB090814A: NOT optical follow-ups
  53. GRB 090814B: Swift/UVOT Upper Limits
  54. GRB 090814B: Swift-XRT detection of a possible afterglow.
  55. GRB 090814A: Swift/UVOT Observations
  56. GRB 090814A, RIMOTS optical upper limits
  57. GRB090814A: VLT spectroscopy
  58. GRB 090814: Enhanced Swift-XRT position
  59. GRB 090814: GROND Detection of an Optical Afterglow Candidate
  60. GRB 090814: Swift detection of a burst
  61. GRB 090813: Fermi GBM observation
  62. Konus-Wind observations of GRB090813
  63. GRB090813: Swift/UVOT upper limits
  64. GRB 090813: Enhanced Swift-XRT position
  65. GRB 090813: P60 Optical Afterglow Confirmation
  66. GRB 090813: Swift detection of a burst
  67. GRB 090812: Faulkes Telescope South Continued Optical Monitoring
  68. GRB 090812: RAPTOR detections during the burst
  69. GRB 090812, RIMOTS optical upper limits
  70. GRB090812: Swift/UVOT observations
  71. GRB 090812: GROND Observations of the Optical/NIR Afterglow
  72. GRB 090812: Enhanced Swift-XRT position
  73. GRB 090812: P60 Confirmation of Optical Afterglow
  74. GRB 090812: Swift detection of a burst with an optical counterpart
  75. GRB 090809: Further NOT optical observations
  76. VLA radio upper limit on GRB 090809
  77. GRB 090809: WHT observations
  78. GRB 090809B: Fermi GBM detection
  79. GRB090809: Swift/UVOT observations
  80. GRB 090809: Enhanced Swift-XRT position
  81. GRB 090809: Swift-BAT refined analysis
  82. GRB 090809: afterglow confirmation at the NOT
  83. GRB 090809: Swift detection of a burst with a possible optical counterpart
  84. GRB 090807: MITSuME optical upper limit
  85. GRB 090807: Swift/UVOT Upper Limits
  86. GRB 090807: Enhanced Swift-XRT position
  87. GRB 090807, RIMOTS optical upper limits
  88. GRB 090807: Swift detection of a burst
  89. GRB 090726: optical observation
  90. Swift trigger 358760 is probably a noise event
  91. GRB 090727: GRT Optical Observation
  92. GRB 090726: GRT Optical Observation
  93. GRB 090727: Swift/UVOT Upper Limits
  94. GRB 090728: Swift/UVOT Upper Limits
  95. GRB 090728: Enhanced Swift-XRT position
  96. GRB 090728, RIMOTS optical upper limits
  97. GRB 090728: Swift detection of a burst
  98. GRB 090727: Enhanced Swift-XRT position
  99. GRB 090715B: Late-time Lick 3m observations
  100. GRB 090727: Swift detection of a burst

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