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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"

26322 results found.

  1. HETE Alert 4006: MASTER promt optical limit
  2. GRB060117 - ATCA 3/6cm radio limits - correction
  3. GRB060117 - ATCA 3/6cm radio limits
  4. GRB 060116: photometric redshift - the farthest GRB?
  5. Konus-Wind observation of GRB 060117
  6. GRB 060116: UKIRT IR Observations
  7. GRB 060117: Refined analysis of the Swift-BAT burst
  8. GRB 060117: FRAM optical afterglow candidate
  9. GRB 060117: nearby galaxy
  10. GRB 060116: VLT optical observations
  11. GRB 060116: Refined analysis of the Swift-BAT burst
  12. GRB 060116: XRT refined analysis
  13. GRB 060116: IR Candidate Afterglow
  14. GRB 060116: Swift/UVOT upper limits
  15. GRB060115: REM observations
  16. GRB 060110: XRT position and analysis
  17. GRB 060116 : Lulin optical limit
  18. GRB060116: Faulkes North observation
  19. GRB 060116: Swift-BAT detection of a burst
  20. GRB 060115: Refined analysis of the Swift-BAT burst
  21. GRB 060115: Swift/UVOT upper limits
  22. GRB 060114: REM observations
  23. GRB 060115: Swift XRT refined analysis
  24. GRB 060114: Swift/UVOT Observations
  25. GRB060115, optical observation
  26. GRB 060115: MITSuME optical afterglow candidate
  27. GRB 060115: Swift detection of a burst
  28. GRB060114, optical observation
  29. GRB060114: Faulkes North observation
  30. GRB 060108: IR observations of afterglow
  31. GRB 060108: Evidence for an XRT Position Offset
  32. GRB 060110: KAIT observations
  33. GRB 060111B: Swift XRT refined analysis
  34. GRB 060111B: MITSuME detection of optical afterglow
  35. GRB 060111B: TAROT optical observation
  36. GRB060111A: RTT150 optical observations
  37. GRB060111B: RTT150, possible host galaxy
  38. GRB 060111B: Refined analysis of the Swift-BAT burst
  39. GRB 060111(a): P60 Observations
  40. GRB 060111B: Gualba observatory limit
  41. GRB 060111B: Swift detection of a burst
  42. GRB 060111: Swift-BAT Refined Analysis
  43. GRB060111.2:_MASTER optical limit
  44. GRB 060108: VLT K-band observations
  45. GRB 060111: TAROT optical observation
  46. GRB 060111: Swift detection of a burst
  47. GRB 060110: Mitsume optical observations
  48. GRB 060110: Swift-BAT refined analysis
  49. GRB 060109: Swift-BAT refined analysis
  50. GRB 060108: z-band imaging from Gemini-North
  51. GRB 060110a: RAPTOR detection of early optical emission.
  52. GRB 060110: UKIRT K-band observations
  53. GRB 060110: IR Candidate Afterglow
  54. GRB060110, optical observation
  55. GRB 060110: Correction
  56. Correction to GRB 060109 XRT analysis
  57. GRB 050110: IR Observations
  58. GRB 060109: Refined Swift-XRT analysis
  59. GRB 060109: Swift/UVOT upper limits
  60. GRB060109, optical observation
  61. GRB 060108: ISAS early observations and near IR upper limit
  62. GRB060108: P200 Ks Observations
  63. GRB 060108: early UKIRT K-band observations
  64. GRB 060108: a dark burst?
  65. GRB 060108: Refined XRT analysis
  66. GRB 060108: VLT J-band observations
  67. GRB 060108: Mitsume optical observations
  68. GRB 060108: Swift/UVOT upper limits
  69. GRB 060105: quick look analysis of the Suzaku/XIS afterglow observation
  70. GRB060108: SDSS pre-burst observations
  71. GRB060108: Faulkes Telescope observation
  72. GRB060108, optical observation
  73. GRB 060108: Refined analysis of the Swift-BAT burst
  74. GRB060108: Swift detection of its 100th GRB
  75. GRB 060105: ISAS observations and near IR upper limit
  76. GRB 060105: Swift/UVOT upper limits
  77. GRB 060105: Mitsume optical observations
  78. GRB 060105: BAT refined analysis
  79. GRB 060105: XRT refined analysis
  80. GRB060105: Suzaku-XIS and -HXD observation plan
  81. GRB060105, optical observation
  82. GRB060105: Swift detection of a bright long burst
  83. Swift-BAT trigger 175653 is probably not a GRB
  84. GRB 060102: Swift-BAT refined analysis
  85. GRB 060102: Swift-BAT detection of a burst
  86. GRB 051221B: Optical Observations with Kuiper 1.54m
  87. GRB 051227: Likely host galaxy underlying afterglow position
  88. GRB 051227: optical observation
  89. GRB 051227: optical afterglow
  90. GRB 051227: Magellan r'-band Imaging/Astrometry
  91. GRB 051227: refined analysis of VLT images
  92. GRB 051227: P60 Observations
  93. GRB 051227: MDM Observation
  94. GRB 051227: R-band object in the XRT error circle
  95. GRB 051227: XRT refined analysis
  96. GRB 051227: Further analysis of the Swift-BAT burst
  97. GRB 051227: Refined analysis of the Swift-BAT burst
  98. GRB051227: SDSS pre-burst observations
  99. GRB 051227, optical observation
  100. GRB051117B: optical observation

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