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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"

25015 results found.

  1. GRB 060117: FRAM optical afterglow candidate
  2. GRB 060117: nearby galaxy
  3. GRB 060116: VLT optical observations
  4. GRB 060116: Refined analysis of the Swift-BAT burst
  5. GRB 060116: XRT refined analysis
  6. GRB 060116: IR Candidate Afterglow
  7. GRB 060116: Swift/UVOT upper limits
  8. GRB060115: REM observations
  9. GRB 060110: XRT position and analysis
  10. GRB 060116 : Lulin optical limit
  11. GRB060116: Faulkes North observation
  12. GRB 060116: Swift-BAT detection of a burst
  13. GRB 060115: Refined analysis of the Swift-BAT burst
  14. GRB 060115: Swift/UVOT upper limits
  15. GRB 060114: REM observations
  16. GRB 060115: Swift XRT refined analysis
  17. GRB 060114: Swift/UVOT Observations
  18. GRB060115, optical observation
  19. GRB 060115: MITSuME optical afterglow candidate
  20. GRB 060115: Swift detection of a burst
  21. GRB060114, optical observation
  22. GRB060114: Faulkes North observation
  23. GRB 060108: IR observations of afterglow
  24. GRB 060108: Evidence for an XRT Position Offset
  25. GRB 060110: KAIT observations
  26. GRB 060111B: Swift XRT refined analysis
  27. GRB 060111B: MITSuME detection of optical afterglow
  28. GRB 060111B: TAROT optical observation
  29. GRB060111A: RTT150 optical observations
  30. GRB060111B: RTT150, possible host galaxy
  31. GRB 060111B: Refined analysis of the Swift-BAT burst
  32. GRB 060111(a): P60 Observations
  33. GRB 060111B: Gualba observatory limit
  34. GRB 060111B: Swift detection of a burst
  35. GRB 060111: Swift-BAT Refined Analysis
  36. GRB060111.2:_MASTER optical limit
  37. GRB 060108: VLT K-band observations
  38. GRB 060111: TAROT optical observation
  39. GRB 060111: Swift detection of a burst
  40. GRB 060110: Mitsume optical observations
  41. GRB 060110: Swift-BAT refined analysis
  42. GRB 060109: Swift-BAT refined analysis
  43. GRB 060108: z-band imaging from Gemini-North
  44. GRB 060110a: RAPTOR detection of early optical emission.
  45. GRB 060110: UKIRT K-band observations
  46. GRB 060110: IR Candidate Afterglow
  47. GRB060110, optical observation
  48. GRB 060110: Correction
  49. Correction to GRB 060109 XRT analysis
  50. GRB 050110: IR Observations
  51. GRB 060109: Refined Swift-XRT analysis
  52. GRB 060109: Swift/UVOT upper limits
  53. GRB060109, optical observation
  54. GRB 060108: ISAS early observations and near IR upper limit
  55. GRB060108: P200 Ks Observations
  56. GRB 060108: early UKIRT K-band observations
  57. GRB 060108: a dark burst?
  58. GRB 060108: Refined XRT analysis
  59. GRB 060108: VLT J-band observations
  60. GRB 060108: Mitsume optical observations
  61. GRB 060108: Swift/UVOT upper limits
  62. GRB 060105: quick look analysis of the Suzaku/XIS afterglow observation
  63. GRB060108: SDSS pre-burst observations
  64. GRB060108: Faulkes Telescope observation
  65. GRB060108, optical observation
  66. GRB 060108: Refined analysis of the Swift-BAT burst
  67. GRB060108: Swift detection of its 100th GRB
  68. GRB 060105: ISAS observations and near IR upper limit
  69. GRB 060105: Swift/UVOT upper limits
  70. GRB 060105: Mitsume optical observations
  71. GRB 060105: BAT refined analysis
  72. GRB 060105: XRT refined analysis
  73. GRB060105: Suzaku-XIS and -HXD observation plan
  74. GRB060105, optical observation
  75. GRB060105: Swift detection of a bright long burst
  76. Swift-BAT trigger 175653 is probably not a GRB
  77. GRB 060102: Swift-BAT refined analysis
  78. GRB 060102: Swift-BAT detection of a burst
  79. GRB 051221B: Optical Observations with Kuiper 1.54m
  80. GRB 051227: Likely host galaxy underlying afterglow position
  81. GRB 051227: optical observation
  82. GRB 051227: optical afterglow
  83. GRB 051227: Magellan r'-band Imaging/Astrometry
  84. GRB 051227: refined analysis of VLT images
  85. GRB 051227: P60 Observations
  86. GRB 051227: MDM Observation
  87. GRB 051227: R-band object in the XRT error circle
  88. GRB 051227: XRT refined analysis
  89. GRB 051227: Further analysis of the Swift-BAT burst
  90. GRB 051227: Refined analysis of the Swift-BAT burst
  91. GRB051227: SDSS pre-burst observations
  92. GRB 051227, optical observation
  93. GRB051117B: optical observation
  94. Konus-Wind observation of GRB 051221A
  95. GRB051221A: Suzaku WAM observation of the prompt emission
  96. GRB 051221A: MDM Optical Observations
  97. GRB051016: analysis of the XMM-Newton observation
  98. GRB 051221A: Refined spectral and temporal analysis of the Swift-BAT short hard burst
  99. GRB 051221B: TAROT optical limits
  100. GRB 051221B: Refined analysis of the Swift-BAT burst

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