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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"

19128 results found.

  1. GRB060210: Swift XRT Refined Analysis
  2. GRB060210: Early Optical Observations
  3. GRB060210:Faulkes Telescope North Afterglow Confirmation
  4. GRB 060210: candidate afterglow
  5. GRB 060210: Swift detection of a burst
  6. GRB060210: Optical afterglow
  7. GRB 060206: Swift/UVOT Observations
  8. Swift-BAT trigger 180931 is not a GRB
  9. GRB060209: RTT150 optical observations
  10. GRB 060209 : TAROT optical observation
  11. GRB 060209(?): Swift-BAT detection of a possible burst
  12. GRB 060206: WSRT Radio Observations
  13. GRB 060203: Swift/UVOT upper limits
  14. GRB060204a: Swift XRT Source is not GRB Afterglow
  15. GRB 060204b: pseudo-z from spectral parameters of the prompt emission
  16. GRB 060204A: ROSAT Pointing
  17. GRB060204A: Swift/UVOT observations
  18. GRB 060206: Swift-BAT refined analysis
  19. GRB060206: Swift XRT Refined Analysis
  20. GRB060206: Swift XRT Position
  21. GRB060204a: Swift XRT Detection of an Afterglow Candidate
  22. GRB060206 - Swift UVOT Confirmation of Optical Afterglow
  23. GRB060206: Swift-BAT detection of a burst
  24. GRB 060204C: XRT analysis of Swift J061223.0+701243.9
  25. BAT GRB 060204C is probably not a GRB
  26. GRB 060204B: BVRi-band detections of optical afterglow
  27. GRB 060204A: Swift XRT upper limit
  28. GRB060204B: Swift/UVOT refined analysis
  29. Swift XRT Observation of GRB 060204C
  30. GRB 060204B: Swift-BAT refined analysis
  31. GRB060204B: Swift XRT Team Refined Analysis
  32. GRB 060204C: OSN limits
  33. GRB 060204C: Liverpool Telescopes optical limit
  34. GRB 060204C: ROTSE-III Optical Limits
  35. GRB 060204C: Swift-BAT detection of a burst
  36. GRB 060124: Radio Observations
  37. GRB060204B: Faulkes OT candidate
  38. GRB060204B, optical observation
  39. GRB060204B - SDSS pre-burst observations
  40. GRB 060203: Swift-BAT refined analysis
  41. GRB 060204B: Swift detection of a burst
  42. GRB 060203: RTT150 optical observations
  43. GRB060203: Swift XRT Team Refined Analysis
  44. GRB060203 - Swift UVOT observation
  45. Swift-BAT trigger is GRB 060203
  46. GRB060203: Observations with SARA
  47. GRB 060203: P60 Confirmation of Optical Afterglow
  48. Possible GRB 060203: candidate optical counterpart
  49. Swift BAT Trigger 180151: Swift XRT source detection
  50. Possible GRB 060203: optical observations at Asiago
  51. Swift-BAT trigger 180151 is unknown origin at this time
  52. GRB 060202: Refined analysis of the Swift-BAT burst
  53. GRB060202, optical observation
  54. GRB 060202: Swift/UVOT upper limits
  55. GRB 060202: Swift XRT Team Refined Analysis
  56. GRB060202: Faulkes North observation
  57. GRB 060202: Swift detection of a burst
  58. GRB 060130: Swift/XRT observation
  59. GRB 060123: VLA Radio Observations
  60. Possible GRB 051221B: MDM Correction
  61. GRB 060123: Swift refined analysis of an unusual GRB
  62. GRB060124, BVRcIc field calibration
  63. GRB060105: refined analysis of the Suzaku observation
  64. GRB 060124: HETE detection and spectrum of the main peak
  65. Konus-Wind observation of GRB 060124
  66. GRB060124: detailed XRT analysis
  67. GRB 060124 Optical Observations
  68. GRB 060124: R band Observations
  69. GRB 060124: Extremely long burst, Swift-BAT refined analysis
  70. GRB 060123: Swift detection of a very long, faint burst
  71. GRB 060124: TAROT optical limits
  72. GRB 060124: Swift/UVOT Observation
  73. GRB 060124: Confirmation of the Afterglow
  74. GRB 060124: XRT position
  75. GRB 060124: Optical Observations at Tautenburg
  76. GRB 060117: Suzaku WAM observation of the prompt emission
  77. GRB060124:MASTER optical observation
  78. GRB 060111B: Suzaku WAM observation of the prompt emission
  79. GRB 060124: Swift-BAT detection of a burst
  80. GRB 060116: Radio Detection
  81. GRB 060116: MARGE optical observations
  82. GRB 060121: Swift/UVOT upper limits
  83. GRB 060121: Liverpool Telescopes optical limits
  84. GRB 060121: Swift XRT refined analysis
  85. GRB 060121: Swift XRT refined position
  86. GRB 060117: pseudo-z from spectral parameters of the prompt emission
  87. Konus-Wind observation of GRB 060117
  88. GRB 060117: Refined analysis of the Swift-BAT burst
  89. GRB 060117: FRAM optical afterglow candidate
  90. GRB 060117: Swift-BAT detection of a bright burst
  91. GRB 060116: Refined analysis of the Swift-BAT burst
  92. GRB 060116: Swift/UVOT upper limits
  93. GRB060115: REM observations
  94. GRB 060110: XRT position and analysis
  95. GRB 060116: ROTSE-III Optical Limits
  96. GRB060116: XRT position
  97. GRB060116: Faulkes North observation
  98. GRB 060116: Swift-BAT detection of a burst
  99. GRB 060115: Refined analysis of the Swift-BAT burst
  100. GRB 060115: Swift/UVOT upper limits

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