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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"

19430 results found.

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

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