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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"

18652 results found.

  1. GRB050319, optical observations
  2. GRB050319, color indices
  3. GRB050319: RTT150 Optical Observations
  4. Swift-BAT detection of a bright outburst from SGR1806-20
  5. Swift-BAT trigger 112060 is not a real GRB
  6. GRB 050319: ROTSE-III Refined Analysis
  7. GRB 050318: Swift-BAT refined analysis
  8. Refined Swift XRT positions for GRB050315, GRB050318 and GRB050319
  9. GRB 050319 R band observations
  10. GRB 050319: Swift-UVOT detection of the afterglow
  11. GRB 050315: Variability Analysis of Swift BAT Time History
  12. GRB050319: BR optical photometry
  13. GRB 050318: SWIFT-UVOT refined analysis
  14. GRB 050319: Swift-BAT refined analysis
  15. GRB050319,optical observation
  16. Swift Detection of GRB 050319
  17. GRB 050319: Detection of Possible Optical Counterpart
  18. GRB 050318: Swift/UVOT detection of afterglow emission
  19. GRB050318: Swift XRT position
  20. Swift-BAT detection of GRB 050318
  21. GRB050223: analysis of the XMM-Newton observation
  22. GRB 050306: ROTSE-III early limits
  23. GRB 050315: Swift-BAT further refined analysis
  24. GRB050315: Swift-BAT Refined analysis
  25. Non-detection of GRB050315 in ATCA Radio Observations
  26. GRB 050315: Swift XRT Position
  27. GRB 050315: Early Observations with Swift/UVOT
  28. Swift-BAT detection of GRB 050315
  29. GRB050223: No XMM-Newton OM detection of afterglow emission
  30. GRB050309: CONCAM pre-trigger and trigger coincident optical
  31. GRB 050126: Redshift determination
  32. Swift-BAT trigger 107873: No Swift XRT counterpart
  33. GRB 050306: Confirmation of X-ray afterglow
  34. GRB 050309, Early optical limits from RAPTOR
  35. Swift-BAT trigger 107873 (GRB050309): possible X-ray counterparts
  36. GRB 050309 : Lulin R-band observation
  37. Swift 107873: P60 Optical Observations
  38. GRB 050306: CORRECTION to date of observation
  39. GRB 050306: No Swift UVOT Optical Counterpart Detected
  40. GRB 050306: Possible X-ray Afterglow Position from the Swift
  41. Swift trigger 107518: optical observation
  42. GRB 050306,optical observation
  43. GRB 050306: Swift-BAT detection of a long burst
  44. GRB050215B: Late-Time Swift UVOT Observations
  45. PROMPT VRcIc Observations of GRB 050223
  46. GRB 050223: optical observations
  47. GRB050223 XMM-Newton observation
  48. INTEGRAL detection of GRB 050223
  49. GRB050223: No Swift UVOT Detection of Afterglow Emission
  50. GRB050223: ROTSE-III Optical Observations
  51. GRB 050223 Swift/BAT detection of a burst
  52. GRB 050223: Swift XRT Position
  53. GRB050219b: CORRECTION to time of UVOT observations
  54. GRB050219b: No Swift UVOT Detection of Afterglow Emission
  55. GRB 050219b: CORRECTION to refined XRT position
  56. GRB050219b: No Swift UVOT Detection of Afterglow Emission
  57. GRB 050219b: Refined XRT position
  58. GRB 050219b: Swift-BAT detection of a burst
  59. GRB 050219b: CORRECTION: Swift XRT Position
  60. GRB 050219b: Swift XRT Position
  61. GRB 050219a, optical observations
  62. GRB 050219a: Refined XRT position
  63. GRB050219a: No Swift UVOT Detection of Afterglow Emission
  64. GRB 050219: Swift-BAT detection of a burst
  65. GRB050215b: Swift UVOT Detection of Afterglow Emission
  66. GRB 050219: Prompt X-ray position
  67. GRB 050215b: XRT confirmation of IR afterglow candidate
  68. GRB050215b: P60 Optical Observations
  69. GRB 050215b: Swift XRT Source Variability
  70. GRB 050215B: candidate afterglow
  71. GRB 050215b : Lulin follow-up observation
  72. GRB 050215b, BOOTES-2 simultaneous optical observations
  73. GRB 050215B: UKIRT K-band imaging
  74. GRB 050215b: Swift XRT Observations
  75. GRB050215b: No Swift UVOT Detection of Afterglow Emission
  76. GRB050215a: No Swift UVOT Detection of Afterglow Emission
  77. Swift-BAT detects two bursts: GRB050215a and GRB050215b
  78. GRB050215B: ROTSE-III optical observations
  79. GRB050215A: ROTSE-III Optical Observations
  80. short/hard GRB 050202, optical observations
  81. GRB 050128: Radio observations
  82. Further analysis of the short Swift-BAT GRB 050202
  83. GRB 050202: Second epoch radio observations
  84. GRB050202: Radio Observations
  85. GRB 050202: Short burst detected by Swift-BAT
  86. SGR1806-20: Swift-BAT detection of a large normal burst
  87. GRB050128: Faulkes Telescope South observations
  88. GRB050128,optical observations
  89. GRB050126: Updated Swift XRT Position
  90. GRB 050126: Radio Observations
  91. GRB050128 Swift-BAT observations
  92. GRB 050128: Swift XRT prompt afterglow position
  93. GRB 050124: K-band afterglow observations
  94. GRB050126: MASTER optical limit for KECK OT
  95. GRB050126: Burst Parameters Measured by BAT
  96. GRB050126: MASTER optical observations
  97. GRB 050126: Prompt XRT detection and localization
  98. GRB050124: No Swift UVOT Detection of Afterglow Emission
  99. GRB 050117a: Radio Observations
  100. GRB050124,optical observation

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