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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"

18780 results found.

  1. GRB 050802: Swift-BAT refined analysis
  2. GRB 050802: XRT position
  3. GRB 050802: Swift Gamma-ray Burst
  4. GRB050801: Swift/UVOT Optical and UV detections
  5. GCN 050801: early Swift XRT analysis results
  6. GRB 050801: Swift-BAT refined analysis
  7. GRB 050801, afterglow observations
  8. GRB 050730, corrected photometry and break?
  9. GRB 050801: ROTSE-III Early Afterglow Break
  10. GRB050801: Swift-BAT detection of a burst
  11. GRB050801: GCN XRT position is incorrect
  12. GRB 050801: ROTSE-III Detection of Possible Counterpart
  13. GRB 050730: XRT refined analysis
  14. GRB 050730: early TAROT optical observations
  15. Swift/UVOT photometry of GRB050730
  16. GRB050730: Refined BAT analysis of the Swift-BAT burst
  17. GRB 050730: Swift XRT afterglow observations
  18. GRB 050730 XMM-Newton observation
  19. GRB050730, afterglow observations
  20. GRB 050730: Redshift Measurement based on Magellan/MIKE Observations
  21. GRB050730: Liverpool Telescope optical observations
  22. GRB 050730, optical candidate
  23. GRB050730: Swift-BAT detection of a weak burst
  24. GRB 050713A: Swift XRT extended light curve
  25. GRB050726: Swift UVOT observations
  26. GRB 050724: Chandra Observations of the X-ray Afterglow
  27. GRB050713: analysis of the XMM-Newton observation
  28. Swift-BAT trigger 147918 is not a real GRB
  29. GRB 050727: RTT150 optical observations
  30. GRB050727: KAIT optical limit
  31. GRB 050724: dust-scattered X-ray halo detected in SWIFT/XRT observation
  32. GRB 050726: early Swift XRT analysis results
  33. GRB050726: Swift-BAT detection of a weak burst
  34. GRB 050724: SWIFT XRT refined position
  35. GRB 050724: optical and near-IR observations
  36. GRB 050724: Swift/UVOT Upper Limit
  37. GRB 050724: early Swift XRT analysis results
  38. GRB050724: Refined analysis of the Swift-BAT possible short burst
  39. GRB050724: a short-burst detected by Swift
  40. Swift-BAT trigger 147325 is not due to a real GRB
  41. GRB050723: XRT distributed coordinates are not related to the burst
  42. GRB 050721A: Swift-BAT refined analysis
  43. GRB 050721A: Early Swift XRT analysis results
  44. Swift BAT Trigger 146986 is SWIFT J1753.5-0127
  45. GRB 050721a: Optical Observations
  46. GRB050721A: Swift-BAT detection of a weak burst
  47. GRB 050714a: Refined XRT analysis and afterglow confirmation
  48. Swift-BAT trigger 146731 is not a real GRB
  49. Swift-BAT detection of a possible GRB
  50. GRB050717
  51. Konus-Wind observation of GRB 050717
  52. Swift/UVOT Observations of GRB 050717
  53. GRB 050717: Swift-BAT refined analysis
  54. GRB 050717: Refined XRT analysis.
  55. GRB050712: optical limits
  56. GRB050717: Swift XRT position
  57. Swift detection of GRB 050717
  58. GRB 050716 - UKIRT identification of candidate afterglow
  59. Swift UVOT Observations of GRB 050716
  60. GRB 050716: Refined XRT analysis.
  61. GRB050716: Refined analysis of the Swift-BAT burst
  62. GRB050716, optical observation
  63. GRB050716: Faulkes North Telescope observation
  64. GRB050716: Correction to sign in XRT coordinate
  65. Swift/BAT detection of GRB 050716
  66. GRB050715: Refined analysis of the Swift-BAT burst
  67. GRB 050715: Swift-BAT detection
  68. Swift UVOT Observations of GRB 050714B
  69. Konus-Wind observation of GRB 050713A
  70. GRB 050714B: refined XRT analysis
  71. GRB050714B: Refined analysis of the Swift-BAT burst
  72. Swift detection of a long transient (GRB 050714B?)
  73. GRB 050714: Swift XRT afterglow position
  74. GRB 050713A: XRT refined analysis
  75. GRB 050713A: RAPTOR detection of early optical emission
  76. GRB050713B :Swift/UVOT observations
  77. GRB050713b: XRT refined analysis
  78. GRB 050713B: Swift-BAT Refined Analysis
  79. Swift-BAT Trigger 145729 is not a GRB
  80. GRB 050713A: Swift/UVOT observation
  81. GRB 050713A : Swift-BAT Refined Analysis
  82. GRB050712: Swift UVOT Observation of Afterglow Emission
  83. GRB 050713A XMM-Newton observation
  84. GRB050713B: Faulkes North Telescope observation
  85. RBO RI observations of GRB 050713A
  86. GRB 050713B
  87. GRB050713: Liverpool Telescope prompt observations
  88. GRB050709: Candidate X-ray Afterglow from Chandra
  89. GRB 050713, R-band observations at NOT
  90. GRB 050713: Swift detection of Bright Burst
  91. GRB 050713A: ROTSE-III Optical Limits
  92. GRB050712: XRT refined analysis
  93. GRB 050709: Swift UVOT and XRT observations
  94. GRB 050712: Swift-BAT Refined Analysis
  95. GRB050712: UVOT candidate optical counterpart
  96. GRB 050712: Swift XRT afterglow position
  97. GRB 050712: Swift detection of a weak burst
  98. GRB 050525a: ARC 3.5-meter Optical and NIR Observations
  99. GRB 050626: Swift XRT observations
  100. GRB 050701

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