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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"

18476 results found.

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

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