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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"

19187 results found.

  1. GRB050803: Swift-BAT detection of a very long burst
  2. GCN GRB observation 050713A
  3. GRB 050802: Swift/UVOT optical and UV detections
  4. GRB050802 radio non-detection
  5. GRB 050730: OHP optical observations
  6. GRB 050802: early Swift XRT analysis results
  7. GRB 050802: Swift/UVOT observations
  8. GRB 050802: Swift-BAT refined analysis
  9. GRB 050802: XRT position
  10. GRB 050802: Swift Gamma-ray Burst
  11. GRB050801: Swift/UVOT Optical and UV detections
  12. GCN 050801: early Swift XRT analysis results
  13. GRB 050801: Swift-BAT refined analysis
  14. GRB 050801, afterglow observations
  15. GRB 050730, corrected photometry and break?
  16. GRB 050801: ROTSE-III Early Afterglow Break
  17. GRB050801: Swift-BAT detection of a burst
  18. GRB050801: GCN XRT position is incorrect
  19. GRB 050801: ROTSE-III Detection of Possible Counterpart
  20. GRB 050730: XRT refined analysis
  21. GRB 050730: early TAROT optical observations
  22. Swift/UVOT photometry of GRB050730
  23. GRB050730: Refined BAT analysis of the Swift-BAT burst
  24. GRB 050730: Swift XRT afterglow observations
  25. GRB 050730 XMM-Newton observation
  26. GRB050730, afterglow observations
  27. GRB 050730: Redshift Measurement based on Magellan/MIKE Observations
  28. GRB050730: Liverpool Telescope optical observations
  29. GRB 050730, optical candidate
  30. GRB050730: Swift-BAT detection of a weak burst
  31. GRB 050713A: Swift XRT extended light curve
  32. GRB050726: Swift UVOT observations
  33. GRB 050724: Chandra Observations of the X-ray Afterglow
  34. GRB050713: analysis of the XMM-Newton observation
  35. Swift-BAT trigger 147918 is not a real GRB
  36. GRB 050727: RTT150 optical observations
  37. GRB050727: KAIT optical limit
  38. GRB 050724: dust-scattered X-ray halo detected in SWIFT/XRT observation
  39. GRB 050726: early Swift XRT analysis results
  40. GRB050726: Swift-BAT detection of a weak burst
  41. GRB 050724: SWIFT XRT refined position
  42. GRB 050724: optical and near-IR observations
  43. GRB 050724: Swift/UVOT Upper Limit
  44. GRB 050724: early Swift XRT analysis results
  45. GRB050724: Refined analysis of the Swift-BAT possible short burst
  46. GRB050724: a short-burst detected by Swift
  47. Swift-BAT trigger 147325 is not due to a real GRB
  48. GRB050723: XRT distributed coordinates are not related to the burst
  49. GRB 050721A: Swift-BAT refined analysis
  50. GRB 050721A: Early Swift XRT analysis results
  51. Swift BAT Trigger 146986 is SWIFT J1753.5-0127
  52. GRB 050721a: Optical Observations
  53. GRB050721A: Swift-BAT detection of a weak burst
  54. GRB 050714a: Refined XRT analysis and afterglow confirmation
  55. Swift-BAT trigger 146731 is not a real GRB
  56. Swift-BAT detection of a possible GRB
  57. GRB050717
  58. Konus-Wind observation of GRB 050717
  59. Swift/UVOT Observations of GRB 050717
  60. GRB 050717: Swift-BAT refined analysis
  61. GRB 050717: Refined XRT analysis.
  62. GRB050712: optical limits
  63. GRB050717: Swift XRT position
  64. Swift detection of GRB 050717
  65. GRB 050716 - UKIRT identification of candidate afterglow
  66. Swift UVOT Observations of GRB 050716
  67. GRB 050716: Refined XRT analysis.
  68. GRB050716: Refined analysis of the Swift-BAT burst
  69. GRB050716, optical observation
  70. GRB050716: Faulkes North Telescope observation
  71. GRB050716: Correction to sign in XRT coordinate
  72. Swift/BAT detection of GRB 050716
  73. GRB050715: Refined analysis of the Swift-BAT burst
  74. GRB 050715: Swift-BAT detection
  75. Swift UVOT Observations of GRB 050714B
  76. Konus-Wind observation of GRB 050713A
  77. GRB 050714B: refined XRT analysis
  78. GRB050714B: Refined analysis of the Swift-BAT burst
  79. Swift detection of a long transient (GRB 050714B?)
  80. GRB 050714: Swift XRT afterglow position
  81. GRB 050713A: XRT refined analysis
  82. GRB 050713A: RAPTOR detection of early optical emission
  83. GRB050713B :Swift/UVOT observations
  84. GRB050713b: XRT refined analysis
  85. GRB 050713B: Swift-BAT Refined Analysis
  86. Swift-BAT Trigger 145729 is not a GRB
  87. GRB 050713A: Swift/UVOT observation
  88. GRB 050713A : Swift-BAT Refined Analysis
  89. GRB050712: Swift UVOT Observation of Afterglow Emission
  90. GRB 050713A XMM-Newton observation
  91. GRB050713B: Faulkes North Telescope observation
  92. RBO RI observations of GRB 050713A
  93. GRB 050713B
  94. GRB050713: Liverpool Telescope prompt observations
  95. GRB050709: Candidate X-ray Afterglow from Chandra
  96. GRB 050713, R-band observations at NOT
  97. GRB 050713: Swift detection of Bright Burst
  98. GRB 050713A: ROTSE-III Optical Limits
  99. GRB050712: XRT refined analysis
  100. GRB 050709: Swift UVOT and XRT observations

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