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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"

19150 results found.

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

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