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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"

19073 results found.

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

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