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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"

25907 results found.

  1. GRB060206 - Swift UVOT Confirmation of Optical Afterglow
  2. GRB060206: Optical afterglow
  3. GRB060206: Swift-BAT detection of a burst
  4. GRB 060204C: XRT analysis of Swift J061223.0+701243.9
  5. BAT GRB 060204C is probably not a GRB
  6. GRB 060204B: BVRi-band detections of optical afterglow
  7. GRB 060204A: Swift XRT upper limit
  8. GRB060204B: Swift/UVOT refined analysis
  9. GRB 060204C: optical observations
  10. Swift XRT Observation of GRB 060204C
  11. GRB 060204B: Swift-BAT refined analysis
  12. GRB 060204B: ART early limit
  13. GRB060204B: Swift XRT Team Refined Analysis
  14. GRB 060204C: OSN limits
  15. GRB 060204b: Keck/LRIS Afterglow Confirmation
  16. GRB 060204C: Liverpool Telescopes optical limit
  17. GRB 060204C: ROTSE-III Optical Limits
  18. GRB 060204C: Swift-BAT detection of a burst
  19. GRB 060124: Radio Observations
  20. GRB060204B: Faulkes OT candidate
  21. GRB 060204B: ART optical limit
  22. GRB060204B, optical observation
  23. GRB060204B - SDSS pre-burst observations
  24. GRB 060203: Swift-BAT refined analysis
  25. GRB 060204B: Swift detection of a burst
  26. GRB 060202: UKIRT/WFCAM K-band and KeckI/LRIS I-band Observation
  27. GRB 060203: RTT150 optical observations
  28. GRB060203: Swift XRT Team Refined Analysis
  29. GRB060203 - Swift UVOT observation
  30. Swift-BAT trigger is GRB 060203
  31. GRB 060203: IR Counterpart
  32. GRB060203: Observations with SARA
  33. GRB 060203: P60 Confirmation of Optical Afterglow
  34. Possible GRB 060203: candidate optical counterpart
  35. Swift BAT Trigger 180151: Swift XRT source detection
  36. Possible GRB 060203: optical observations at Asiago
  37. Swift-BAT trigger 180151 is unknown origin at this time
  38. GRB 060202: GETS observation
  39. GRB 060202: Gemini-N J, H, K_s observations
  40. GRB 060202 : Kiso B and R band limit
  41. GRB 060202: Near-IR Observation with UKIRT/WFCAM
  42. GRB 060202: Optical Afterglow Candidate from Keck/LRIS
  43. GRB 060202: Refined analysis of the Swift-BAT burst
  44. GRB060202, optical observation
  45. GRB 060202: Swift/UVOT upper limits
  46. GRB 060202: Swift XRT Team Refined Analysis
  47. GRB 060202 : Lulin R and I band limit
  48. GRB060202: Faulkes North observation
  49. GRB 060202: Swift detection of a burst
  50. GRB 060121: Gemini Late-time Observations
  51. GRB 060130: Swift/XRT observation
  52. GRB 051211A: MDM Observations
  53. GRB 060123: Gemini spectroscopy of the putative host galaxy
  54. GRB 060123: VLA Radio Observations
  55. Possible GRB 051221B: MDM Correction
  56. GRB 060121: Confirmation of NIR Afterglow
  57. GRB060124: optical observation
  58. GRB060124: optical observations
  59. GRB 060123: Swift refined analysis of an unusual GRB
  60. GRB060124, BVRcIc field calibration
  61. GRB060105: refined analysis of the Suzaku observation
  62. GRB 060121: Probable Detection of NIR Afterglow
  63. GRB060124: optical observation
  64. GRB 060116 HST observations
  65. GRB 060124: HETE detection and spectrum of the main peak
  66. Refined XRT Position for GRB 060123
  67. Konus-Wind observation of GRB 060124
  68. GRB060124: detailed XRT analysis
  69. GRB 060124 Optical Observations
  70. GRB 060124: ART optical limits during the burst
  71. GRB060123: Optical and IR Imaging
  72. GRB 060123: P200 Observations
  73. GRB 060124: Keck optical spectrum
  74. GRB 060124: MDM Optical Spectrum
  75. GRB 060124: XRT refined analysis
  76. GRB 060124: R band Observations
  77. GRB 060124: Extremely long burst, Swift-BAT refined analysis
  78. GRB 060123: Swift detection of a very long, faint burst
  79. GRB 060116: Further analysis of VLT photometry and optical spectroscopy
  80. GRB 060124: TAROT optical limits
  81. GRB 060124: Swift/UVOT Observation
  82. GRB 060124: Confirmation of the Afterglow
  83. GRB 060124: XRT position
  84. GRB 060124: Optical Afterglow Candidate from Tautenburg
  85. GRB 060124: Optical Observations at Tautenburg
  86. GRB 060117: Suzaku WAM observation of the prompt emission
  87. GRB060124:MASTER optical observation
  88. GRB 060111B: Suzaku WAM observation of the prompt emission
  89. GRB 060124: Swift-BAT detection of a burst
  90. GRB 060116: Radio Detection
  91. GRB 060116: MARGE optical observations
  92. GRB 060121: Swift/UVOT upper limits
  93. GRB 060121: Liverpool Telescopes optical limits
  94. GRB 060121: Swift XRT refined analysis
  95. GRB 060121: I-band Limits
  96. GRB 060121: Confirmation of Afterglow
  97. GRB 060121: candidate optical counterpart
  98. GRB 060121: Swift XRT refined position
  99. GRB 060117: PROMPT Observations
  100. GRB060117 - ATCA 3/6cm radio limits

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