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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"

18568 results found.

  1. Retraction of three Swift GRB triggers
  2. Swift-BAT detection of GRB 050331b
  3. GRB 050331: Swift UVOT Source
  4. Swift-BAT detection of GRB 050331
  5. GRB 050331: Swift XRT Position
  6. Swift Data Publicly Available Starting April 5, 2005
  7. Konus-Wind observation of GRB 050326
  8. GRB050326: optical limit
  9. GRB 050326: Early observations with Swift-UVOT
  10. GRB 050326 XMM-Newton observation
  11. GRB 050326 : Planned XMM-Newton observation
  12. GRB 050326: Swift XRT Position
  13. GRB050326: optical limit 33min before GRB
  14. GRB 050326 BAT refined analysis
  15. GRB050326: delayed XRT observation
  16. Swift-BAT detection of a bright GRB 050326
  17. GRB050319, optical observations
  18. GRB050319, color indices
  19. GRB050319: RTT150 Optical Observations
  20. Swift-BAT detection of a bright outburst from SGR1806-20
  21. Swift-BAT trigger 112060 is not a real GRB
  22. GRB 050319: ROTSE-III Refined Analysis
  23. GRB 050318: Swift-BAT refined analysis
  24. Refined Swift XRT positions for GRB050315, GRB050318 and GRB050319
  25. GRB 050319 R band observations
  26. GRB 050319: Swift-UVOT detection of the afterglow
  27. GRB 050315: Variability Analysis of Swift BAT Time History
  28. GRB050319: BR optical photometry
  29. GRB 050318: SWIFT-UVOT refined analysis
  30. GRB 050319: Swift-BAT refined analysis
  31. GRB050319,optical observation
  32. Swift Detection of GRB 050319
  33. GRB 050319: Detection of Possible Optical Counterpart
  34. GRB 050318: Swift/UVOT detection of afterglow emission
  35. GRB050318: Swift XRT position
  36. Swift-BAT detection of GRB 050318
  37. GRB050223: analysis of the XMM-Newton observation
  38. GRB 050306: ROTSE-III early limits
  39. GRB 050315: Swift-BAT further refined analysis
  40. GRB050315: Swift-BAT Refined analysis
  41. Non-detection of GRB050315 in ATCA Radio Observations
  42. GRB 050315: Swift XRT Position
  43. GRB 050315: Early Observations with Swift/UVOT
  44. Swift-BAT detection of GRB 050315
  45. GRB050223: No XMM-Newton OM detection of afterglow emission
  46. GRB050309: CONCAM pre-trigger and trigger coincident optical
  47. GRB 050126: Redshift determination
  48. Swift-BAT trigger 107873: No Swift XRT counterpart
  49. GRB 050306: Confirmation of X-ray afterglow
  50. GRB 050309, Early optical limits from RAPTOR
  51. Swift-BAT trigger 107873 (GRB050309): possible X-ray counterparts
  52. GRB 050309 : Lulin R-band observation
  53. Swift 107873: P60 Optical Observations
  54. GRB 050306: CORRECTION to date of observation
  55. GRB 050306: No Swift UVOT Optical Counterpart Detected
  56. GRB 050306: Possible X-ray Afterglow Position from the Swift
  57. Swift trigger 107518: optical observation
  58. GRB 050306,optical observation
  59. GRB 050306: Swift-BAT detection of a long burst
  60. GRB050215B: Late-Time Swift UVOT Observations
  61. PROMPT VRcIc Observations of GRB 050223
  62. GRB 050223: optical observations
  63. GRB050223 XMM-Newton observation
  64. INTEGRAL detection of GRB 050223
  65. GRB050223: No Swift UVOT Detection of Afterglow Emission
  66. GRB050223: ROTSE-III Optical Observations
  67. GRB 050223 Swift/BAT detection of a burst
  68. GRB 050223: Swift XRT Position
  69. GRB050219b: CORRECTION to time of UVOT observations
  70. GRB050219b: No Swift UVOT Detection of Afterglow Emission
  71. GRB 050219b: CORRECTION to refined XRT position
  72. GRB050219b: No Swift UVOT Detection of Afterglow Emission
  73. GRB 050219b: Refined XRT position
  74. GRB 050219b: Swift-BAT detection of a burst
  75. GRB 050219b: CORRECTION: Swift XRT Position
  76. GRB 050219b: Swift XRT Position
  77. GRB 050219a, optical observations
  78. GRB 050219a: Refined XRT position
  79. GRB050219a: No Swift UVOT Detection of Afterglow Emission
  80. GRB 050219: Swift-BAT detection of a burst
  81. GRB050215b: Swift UVOT Detection of Afterglow Emission
  82. GRB 050219: Prompt X-ray position
  83. GRB 050215b: XRT confirmation of IR afterglow candidate
  84. GRB050215b: P60 Optical Observations
  85. GRB 050215b: Swift XRT Source Variability
  86. GRB 050215B: candidate afterglow
  87. GRB 050215b : Lulin follow-up observation
  88. GRB 050215b, BOOTES-2 simultaneous optical observations
  89. GRB 050215B: UKIRT K-band imaging
  90. GRB 050215b: Swift XRT Observations
  91. GRB050215b: No Swift UVOT Detection of Afterglow Emission
  92. GRB050215a: No Swift UVOT Detection of Afterglow Emission
  93. Swift-BAT detects two bursts: GRB050215a and GRB050215b
  94. GRB050215B: ROTSE-III optical observations
  95. GRB050215A: ROTSE-III Optical Observations
  96. short/hard GRB 050202, optical observations
  97. GRB 050128: Radio observations
  98. Further analysis of the short Swift-BAT GRB 050202
  99. GRB 050202: Second epoch radio observations
  100. GRB050202: Radio Observations

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