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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"

28068 results found.

  1. GRB 060204C: Swift-BAT detection of a burst
  2. GRB 060124: Radio Observations
  3. GRB060204B: Faulkes OT candidate
  4. GRB 060204B: ART optical limit
  5. GRB 060204B: Swift detection of a burst
  6. GRB 060202: UKIRT/WFCAM K-band and KeckI/LRIS I-band Observation
  7. GRB 060203: RTT150 optical observations
  8. GRB060203: Swift XRT Team Refined Analysis
  9. GRB060203 - Swift UVOT observation
  10. Swift-BAT trigger is GRB 060203
  11. GRB 060203: IR Counterpart
  12. GRB 060203: P60 Confirmation of Optical Afterglow
  13. Possible GRB 060203: candidate optical counterpart
  14. Swift BAT Trigger 180151: Swift XRT source detection
  15. Swift-BAT trigger 180151 is unknown origin at this time
  16. GRB 060202: GETS observation
  17. GRB 060202: Gemini-N J, H, K_s observations
  18. GRB 060202 : Kiso B and R band limit
  19. GRB 060202: Near-IR Observation with UKIRT/WFCAM
  20. GRB 060202: Optical Afterglow Candidate from Keck/LRIS
  21. GRB 060202: Refined analysis of the Swift-BAT burst
  22. GRB 060202: Swift/UVOT upper limits
  23. GRB 060202: Swift XRT Team Refined Analysis
  24. GRB 060202 : Lulin R and I band limit
  25. GRB060202: Faulkes North observation
  26. GRB 060202: Swift detection of a burst
  27. GRB 060121: Gemini Late-time Observations
  28. GRB 060130: Swift/XRT observation
  29. GRB 051211A: MDM Observations
  30. GRB 060123: Gemini spectroscopy of the putative host galaxy
  31. GRB 060123: VLA Radio Observations
  32. GRB060130: Optical imaging
  33. GRB 060130, SMARTS optical observations
  34. Possible GRB 051221B: MDM Correction
  35. GRB 060121: Confirmation of NIR Afterglow
  36. GRB060124: optical observation
  37. GRB060124: optical observations
  38. GRB 060123: Swift refined analysis of an unusual GRB
  39. GRB060124, BVRcIc field calibration
  40. GRB060105: refined analysis of the Suzaku observation
  41. GRB 060121: Probable Detection of NIR Afterglow
  42. GRB060124: optical observation
  43. GRB 060116 HST observations
  44. GRB 060124: HETE detection and spectrum of the main peak
  45. Refined XRT Position for GRB 060123
  46. GRB060124: detailed XRT analysis
  47. GRB 060124: ART optical limits during the burst
  48. GRB060123: Optical and IR Imaging
  49. GRB 060123: P200 Observations
  50. GRB 060124: Keck optical spectrum
  51. GRB 060124: MDM Optical Spectrum
  52. GRB 060124: XRT refined analysis
  53. GRB 060123: Swift detection of a very long, faint burst
  54. GRB 060116: Further analysis of VLT photometry and optical spectroscopy
  55. GRB 060124: Confirmation of the Afterglow
  56. GRB 060124: XRT position
  57. GRB 060124: Optical Afterglow Candidate from Tautenburg
  58. GRB 060124: Optical Observations at Tautenburg
  59. GRB 060124: Swift-BAT detection of a burst
  60. GRB 060116: Radio Detection
  61. GRB 060121: Swift/UVOT upper limits
  62. GRB 060121: Liverpool Telescopes optical limits
  63. GRB 060121: Swift XRT refined analysis
  64. GRB 060121: I-band Limits
  65. GRB 060121: Confirmation of Afterglow
  66. GRB 060121: candidate optical counterpart
  67. GRB 060121: Swift XRT refined position
  68. GRB 060121: Infrared Observations
  69. GRB 060117: PROMPT Observations
  70. GRB060117 - ATCA 3/6cm radio limits
  71. GRB 060116: photometric redshift - the farthest GRB?
  72. GRB 060116: possible I-J dropout
  73. GRB060108: photometric redshift determination
  74. GRB 060117: Refined analysis of the Swift-BAT burst
  75. GRB 060116: PROMPT Observations
  76. GRB 060117: FRAM refined analysis
  77. GRB 060117: FRAM optical afterglow candidate
  78. GRB 060117: Swift-BAT detection of a bright burst
  79. GRB 060116: VLT optical observations
  80. GRB 060115: PROMPT Observations
  81. GRB 060116: XRT refined analysis
  82. GRB 060116: IR Candidate Afterglow
  83. GRB 060116: Swift/UVOT upper limits
  84. GRB060115: REM observations
  85. GRB 060110: XRT position and analysis
  86. GRB 060116 : Lulin optical limit
  87. GRB 060116: ROTSE-III Optical Limits
  88. GRB060116: XRT position
  89. GRB060116: Faulkes North observation
  90. GRB 060116: Swift-BAT detection of a burst
  91. GRB 060115: Refined analysis of the Swift-BAT burst
  92. GRB 060115: OT photometry with MITSuME
  93. GRB 060115: Swift/UVOT upper limits
  94. GRB 060115: Swift XRT refined analysis
  95. GRB 060115: OT finding chart
  96. GRB 060115: MITSuME optical afterglow candidate
  97. GRB 060115: Swift detection of a burst
  98. GRB 060114: Swift XRT upper limit
  99. GRB060114: Faulkes North observation
  100. GRB 060108: IR observations of afterglow

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