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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"

20235 results found.

  1. GRB060124, BVRcIc field calibration
  2. GRB060105: refined analysis of the Suzaku observation
  3. GRB 060121: Probable Detection of NIR Afterglow
  4. GRB 060116 HST observations
  5. Konus-Wind observation of GRB 060124
  6. GRB 060124: ART optical limits during the burst
  7. GRB060123: Optical and IR Imaging
  8. GRB 060123: P200 Observations
  9. GRB 060124: R band Observations
  10. GRB 060124 : Optical observation at Xinglong and Kiso
  11. GRB060123: SDSS pre-burst observations
  12. GRB 060123: Swift detection of a very long, faint burst
  13. GRB 060121: OHP optical limits
  14. GRB 060124: TAROT optical limits
  15. GRB060124, optical observation
  16. GRB 060124: Optical Observations at Tautenburg
  17. GRB 060117: Suzaku WAM observation of the prompt emission
  18. GRB 060111B: Suzaku WAM observation of the prompt emission
  19. GRB 060124: Swift-BAT detection of a burst
  20. GRB 060121: Swift/UVOT upper limits
  21. GRB 060121: Liverpool Telescopes optical limits
  22. GRB 060121: Swift XRT refined analysis
  23. Konus-Wind observation of GRB 060121
  24. GRB 060121: I-band Limits
  25. GRB 060121: candidate optical counterpart
  26. GRB 060121: Swift XRT refined position
  27. GRB 060121: Infrared Observations
  28. GRB 060121: optical observations
  29. GRB 060121: Optical imaging
  30. GRB060121 - SDSS pre-burst observations
  31. GRB 060121: A short-hard GRB in a cluster?
  32. HETE Alert 4006: MASTER promt optical limit
  33. GRB 060117: PROMPT Observations
  34. GRB060117 - ATCA 3/6cm radio limits - correction
  35. GRB060117 - ATCA 3/6cm radio limits
  36. Konus-Wind observation of GRB 060117
  37. GRB 060116: UKIRT IR Observations
  38. GRB 060117: Refined analysis of the Swift-BAT burst
  39. GRB 060116: PROMPT Observations
  40. GRB 060117: FRAM optical afterglow candidate
  41. GRB 060117: nearby galaxy
  42. GRB 060116: VLT optical observations
  43. GRB 060115: PROMPT Observations
  44. GRB 060116: IR Candidate Afterglow
  45. GRB 060116: Swift/UVOT upper limits
  46. GRB060115: REM observations
  47. GRB 060116: ROTSE-III Optical Limits
  48. GRB060116: Faulkes North observation
  49. GRB 060116: Swift-BAT detection of a burst
  50. GRB 060115: Refined analysis of the Swift-BAT burst
  51. GRB 060115: Swift/UVOT upper limits
  52. GRB 060114: REM observations
  53. GRB 060114: Swift/UVOT Observations
  54. GRB060115, optical observation
  55. GRB 060115: MITSuME optical afterglow candidate
  56. GRB 060115: Swift detection of a burst
  57. GRB060114, optical observation
  58. GRB060114: Faulkes North observation
  59. GRB 060108: IR observations of afterglow
  60. GRB 060108: Evidence for an XRT Position Offset
  61. GRB 060110: KAIT observations
  62. GRB 060111B: MITSuME detection of optical afterglow
  63. GRB 060111B: TAROT optical observation
  64. GRB060111A: RTT150 optical observations
  65. GRB060111B: RTT150, possible host galaxy
  66. GRB 060110: MARGE observations
  67. GRB 060111(a): P60 Observations
  68. GRB 060111B: Gualba observatory limit
  69. GRB 060111B: ROTSE-III Detection of Optical Counterpart Flare
  70. GRB 060111B: Swift detection of a burst
  71. GRB 060108: VLT K-band observations
  72. GRB 060111: TAROT optical observation
  73. GRB060111 : XRT refined analysis
  74. GRB 060111: ROTSE-III Optical Limits
  75. GRB 060111: Swift detection of a burst
  76. GRB 060110: Mitsume optical observations
  77. GRB 060108: z-band imaging from Gemini-North
  78. GRB 060110a: RAPTOR detection of early optical emission.
  79. GRB 060110: UKIRT K-band observations
  80. GRB 060110: IR Candidate Afterglow
  81. GRB060110, optical observation
  82. GRB 060110: Super-LOTIS observations
  83. GRB 060110: Correction
  84. GRB 050110: IR Observations
  85. GRB 060110: Swift-BAT detection of a burst
  86. GRB 060109: Swift/UVOT upper limits
  87. GRB060109, optical observation
  88. GRB 060108: ISAS early observations and near IR upper limit
  89. GRB060108: P200 Ks Observations
  90. GRB 060108: early UKIRT K-band observations
  91. GRB 060109: Swift Detection of a long burst
  92. GRB 060108: VLT J-band observations
  93. GRB 060108: Mitsume optical observations
  94. GRB 060108: Swift/UVOT upper limits
  95. GRB 060105: quick look analysis of the Suzaku/XIS afterglow observation
  96. GRB060108: SDSS pre-burst observations
  97. GRB060108: Faulkes Telescope observation
  98. GRB060108, optical observation
  99. GRB 060108: Refined analysis of the Swift-BAT burst
  100. GRB060108: Swift detection of its 100th GRB

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