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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"

18672 results found.

  1. GRB 050801: ROTSE-III Early Afterglow Break
  2. GRB050801: Swift-BAT detection of a burst
  3. GRB050801: GCN XRT position is incorrect
  4. GRB 050801: ROTSE-III Detection of Possible Counterpart
  5. GRB 050730: XRT refined analysis
  6. GRB 050730: early TAROT optical observations
  7. Swift/UVOT photometry of GRB050730
  8. GRB050730: Refined BAT analysis of the Swift-BAT burst
  9. GRB 050730: Swift XRT afterglow observations
  10. GRB 050730 XMM-Newton observation
  11. GRB050730, afterglow observations
  12. GRB 050730: Redshift Measurement based on Magellan/MIKE Observations
  13. GRB050730: Liverpool Telescope optical observations
  14. GRB 050730, optical candidate
  15. GRB050730: Swift-BAT detection of a weak burst
  16. GRB 050713A: Swift XRT extended light curve
  17. GRB050726: Swift UVOT observations
  18. GRB 050724: Chandra Observations of the X-ray Afterglow
  19. GRB050713: analysis of the XMM-Newton observation
  20. Swift-BAT trigger 147918 is not a real GRB
  21. GRB 050727: RTT150 optical observations
  22. GRB050727: KAIT optical limit
  23. GRB 050724: dust-scattered X-ray halo detected in SWIFT/XRT observation
  24. GRB 050726: early Swift XRT analysis results
  25. GRB050726: Swift-BAT detection of a weak burst
  26. GRB 050724: SWIFT XRT refined position
  27. GRB 050724: optical and near-IR observations
  28. GRB 050724: Swift/UVOT Upper Limit
  29. GRB 050724: early Swift XRT analysis results
  30. GRB050724: Refined analysis of the Swift-BAT possible short burst
  31. GRB050724: a short-burst detected by Swift
  32. Swift-BAT trigger 147325 is not due to a real GRB
  33. GRB050723: XRT distributed coordinates are not related to the burst
  34. GRB 050721A: Swift-BAT refined analysis
  35. GRB 050721A: Early Swift XRT analysis results
  36. Swift BAT Trigger 146986 is SWIFT J1753.5-0127
  37. GRB 050721a: Optical Observations
  38. GRB050721A: Swift-BAT detection of a weak burst
  39. GRB 050714a: Refined XRT analysis and afterglow confirmation
  40. Swift-BAT trigger 146731 is not a real GRB
  41. Swift-BAT detection of a possible GRB
  42. GRB050717
  43. Konus-Wind observation of GRB 050717
  44. Swift/UVOT Observations of GRB 050717
  45. GRB 050717: Swift-BAT refined analysis
  46. GRB 050717: Refined XRT analysis.
  47. GRB050712: optical limits
  48. GRB050717: Swift XRT position
  49. Swift detection of GRB 050717
  50. GRB 050716 - UKIRT identification of candidate afterglow
  51. Swift UVOT Observations of GRB 050716
  52. GRB 050716: Refined XRT analysis.
  53. GRB050716: Refined analysis of the Swift-BAT burst
  54. GRB050716, optical observation
  55. GRB050716: Faulkes North Telescope observation
  56. GRB050716: Correction to sign in XRT coordinate
  57. Swift/BAT detection of GRB 050716
  58. GRB050715: Refined analysis of the Swift-BAT burst
  59. GRB 050715: Swift-BAT detection
  60. Swift UVOT Observations of GRB 050714B
  61. Konus-Wind observation of GRB 050713A
  62. GRB 050714B: refined XRT analysis
  63. GRB050714B: Refined analysis of the Swift-BAT burst
  64. Swift detection of a long transient (GRB 050714B?)
  65. GRB 050714: Swift XRT afterglow position
  66. GRB 050713A: XRT refined analysis
  67. GRB 050713A: RAPTOR detection of early optical emission
  68. GRB050713B :Swift/UVOT observations
  69. GRB050713b: XRT refined analysis
  70. GRB 050713B: Swift-BAT Refined Analysis
  71. Swift-BAT Trigger 145729 is not a GRB
  72. GRB 050713A: Swift/UVOT observation
  73. GRB 050713A : Swift-BAT Refined Analysis
  74. GRB050712: Swift UVOT Observation of Afterglow Emission
  75. GRB 050713A XMM-Newton observation
  76. GRB050713B: Faulkes North Telescope observation
  77. RBO RI observations of GRB 050713A
  78. GRB 050713B
  79. GRB050713: Liverpool Telescope prompt observations
  80. GRB050709: Candidate X-ray Afterglow from Chandra
  81. GRB 050713, R-band observations at NOT
  82. GRB 050713: Swift detection of Bright Burst
  83. GRB 050713A: ROTSE-III Optical Limits
  84. GRB050712: XRT refined analysis
  85. GRB 050709: Swift UVOT and XRT observations
  86. GRB 050712: Swift-BAT Refined Analysis
  87. GRB050712: UVOT candidate optical counterpart
  88. GRB 050712: Swift XRT afterglow position
  89. GRB 050712: Swift detection of a weak burst
  90. GRB 050525a: ARC 3.5-meter Optical and NIR Observations
  91. GRB 050626: Swift XRT observations
  92. GRB 050701
  93. GRB 050701, optical observations
  94. GRB 050701: Refined XRT analysis
  95. Swift UVOT observations of GRB 050701
  96. GRB050701: Swift-BAT Refined analysis
  97. GRB 050701: Swift XRT afterglow position
  98. Swift trigger 143708 is really GRB 050701
  99. GRB 050525A: Swift Late-Time Decay Rate
  100. CORRECTION: GRB050603 Swift UVOT Afterglow Observations

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