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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"

20255 results found.

  1. GRB 060203: IR Counterpart
  2. GRB060203: Observations with SARA
  3. GRB 060203: P60 Confirmation of Optical Afterglow
  4. Possible GRB 060203: optical observations at Asiago
  5. GRB 060202: Gemini-N J, H, K_s observations
  6. GRB 060202: Near-IR Observation with UKIRT/WFCAM
  7. GRB 060202: Optical Afterglow Candidate from Keck/LRIS
  8. GRB060202, optical observation
  9. GRB 060202: Swift/UVOT upper limits
  10. GRB 060202: Swift detection of a burst
  11. GRB 060121: Gemini Late-time Observations
  12. GRB 060130: PROMPT Observations
  13. GRB060130: Further R-band imaging
  14. GRB 060130: Swift/XRT observation
  15. GRB060130: Optical imaging
  16. GRB060130: REM infrared observations
  17. GRB 060130, SMARTS optical observations
  18. GRB 060130: FRAM optical observations
  19. GRB 060121: Confirmation of NIR Afterglow
  20. GRB 060123: Swift refined analysis of an unusual GRB
  21. GRB060124, BVRcIc field calibration
  22. GRB060105: refined analysis of the Suzaku observation
  23. GRB 060121: Probable Detection of NIR Afterglow
  24. GRB 060116 HST observations
  25. Konus-Wind observation of GRB 060124
  26. GRB 060124: ART optical limits during the burst
  27. GRB060123: Optical and IR Imaging
  28. GRB 060123: P200 Observations
  29. GRB 060124: R band Observations
  30. GRB 060124 : Optical observation at Xinglong and Kiso
  31. GRB060123: SDSS pre-burst observations
  32. GRB 060123: Swift detection of a very long, faint burst
  33. GRB 060121: OHP optical limits
  34. GRB 060124: TAROT optical limits
  35. GRB060124, optical observation
  36. GRB 060124: Optical Observations at Tautenburg
  37. GRB 060117: Suzaku WAM observation of the prompt emission
  38. GRB 060111B: Suzaku WAM observation of the prompt emission
  39. GRB 060124: Swift-BAT detection of a burst
  40. GRB 060121: Swift/UVOT upper limits
  41. GRB 060121: Liverpool Telescopes optical limits
  42. GRB 060121: Swift XRT refined analysis
  43. Konus-Wind observation of GRB 060121
  44. GRB 060121: I-band Limits
  45. GRB 060121: candidate optical counterpart
  46. GRB 060121: Swift XRT refined position
  47. GRB 060121: Infrared Observations
  48. GRB 060121: optical observations
  49. GRB 060121: Optical imaging
  50. GRB060121 - SDSS pre-burst observations
  51. GRB 060121: A short-hard GRB in a cluster?
  52. HETE Alert 4006: MASTER promt optical limit
  53. GRB 060117: PROMPT Observations
  54. GRB060117 - ATCA 3/6cm radio limits - correction
  55. GRB060117 - ATCA 3/6cm radio limits
  56. Konus-Wind observation of GRB 060117
  57. GRB 060116: UKIRT IR Observations
  58. GRB 060117: Refined analysis of the Swift-BAT burst
  59. GRB 060116: PROMPT Observations
  60. GRB 060117: FRAM optical afterglow candidate
  61. GRB 060117: nearby galaxy
  62. GRB 060116: VLT optical observations
  63. GRB 060115: PROMPT Observations
  64. GRB 060116: IR Candidate Afterglow
  65. GRB 060116: Swift/UVOT upper limits
  66. GRB060115: REM observations
  67. GRB 060116: ROTSE-III Optical Limits
  68. GRB060116: Faulkes North observation
  69. GRB 060116: Swift-BAT detection of a burst
  70. GRB 060115: Refined analysis of the Swift-BAT burst
  71. GRB 060115: Swift/UVOT upper limits
  72. GRB 060114: REM observations
  73. GRB 060114: Swift/UVOT Observations
  74. GRB060115, optical observation
  75. GRB 060115: MITSuME optical afterglow candidate
  76. GRB 060115: Swift detection of a burst
  77. GRB060114, optical observation
  78. GRB060114: Faulkes North observation
  79. GRB 060108: IR observations of afterglow
  80. GRB 060108: Evidence for an XRT Position Offset
  81. GRB 060110: KAIT observations
  82. GRB 060111B: MITSuME detection of optical afterglow
  83. GRB 060111B: TAROT optical observation
  84. GRB060111A: RTT150 optical observations
  85. GRB060111B: RTT150, possible host galaxy
  86. GRB 060110: MARGE observations
  87. GRB 060111(a): P60 Observations
  88. GRB 060111B: Gualba observatory limit
  89. GRB 060111B: ROTSE-III Detection of Optical Counterpart Flare
  90. GRB 060111B: Swift detection of a burst
  91. GRB 060108: VLT K-band observations
  92. GRB 060111: TAROT optical observation
  93. GRB060111 : XRT refined analysis
  94. GRB 060111: ROTSE-III Optical Limits
  95. GRB 060111: Swift detection of a burst
  96. GRB 060110: Mitsume optical observations
  97. GRB 060108: z-band imaging from Gemini-North
  98. GRB 060110a: RAPTOR detection of early optical emission.
  99. GRB 060110: UKIRT K-band observations
  100. GRB 060110: IR Candidate Afterglow

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