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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"

19186 results found.

  1. GCN GRB observation 050713A
  2. GRB 050802: Swift/UVOT optical and UV detections
  3. GRB050802 radio non-detection
  4. GRB 050730: OHP optical observations
  5. GRB 050802: early Swift XRT analysis results
  6. GRB 050802: Swift/UVOT observations
  7. GRB 050802: Swift-BAT refined analysis
  8. GRB 050802: XRT position
  9. GRB 050802: Swift Gamma-ray Burst
  10. GRB050801: Swift/UVOT Optical and UV detections
  11. GCN 050801: early Swift XRT analysis results
  12. GRB 050801: Swift-BAT refined analysis
  13. GRB 050801, afterglow observations
  14. GRB 050730, corrected photometry and break?
  15. GRB 050801: ROTSE-III Early Afterglow Break
  16. GRB050801: Swift-BAT detection of a burst
  17. GRB050801: GCN XRT position is incorrect
  18. GRB 050801: ROTSE-III Detection of Possible Counterpart
  19. GRB 050730: XRT refined analysis
  20. GRB 050730: early TAROT optical observations
  21. Swift/UVOT photometry of GRB050730
  22. GRB050730: Refined BAT analysis of the Swift-BAT burst
  23. GRB 050730: Swift XRT afterglow observations
  24. GRB 050730 XMM-Newton observation
  25. GRB050730, afterglow observations
  26. GRB 050730: Redshift Measurement based on Magellan/MIKE Observations
  27. GRB050730: Liverpool Telescope optical observations
  28. GRB 050730, optical candidate
  29. GRB050730: Swift-BAT detection of a weak burst
  30. GRB 050713A: Swift XRT extended light curve
  31. GRB050726: Swift UVOT observations
  32. GRB 050724: Chandra Observations of the X-ray Afterglow
  33. GRB050713: analysis of the XMM-Newton observation
  34. Swift-BAT trigger 147918 is not a real GRB
  35. GRB 050727: RTT150 optical observations
  36. GRB050727: KAIT optical limit
  37. GRB 050724: dust-scattered X-ray halo detected in SWIFT/XRT observation
  38. GRB 050726: early Swift XRT analysis results
  39. GRB050726: Swift-BAT detection of a weak burst
  40. GRB 050724: SWIFT XRT refined position
  41. GRB 050724: optical and near-IR observations
  42. GRB 050724: Swift/UVOT Upper Limit
  43. GRB 050724: early Swift XRT analysis results
  44. GRB050724: Refined analysis of the Swift-BAT possible short burst
  45. GRB050724: a short-burst detected by Swift
  46. Swift-BAT trigger 147325 is not due to a real GRB
  47. GRB050723: XRT distributed coordinates are not related to the burst
  48. GRB 050721A: Swift-BAT refined analysis
  49. GRB 050721A: Early Swift XRT analysis results
  50. Swift BAT Trigger 146986 is SWIFT J1753.5-0127
  51. GRB 050721a: Optical Observations
  52. GRB050721A: Swift-BAT detection of a weak burst
  53. GRB 050714a: Refined XRT analysis and afterglow confirmation
  54. Swift-BAT trigger 146731 is not a real GRB
  55. Swift-BAT detection of a possible GRB
  56. GRB050717
  57. Konus-Wind observation of GRB 050717
  58. Swift/UVOT Observations of GRB 050717
  59. GRB 050717: Swift-BAT refined analysis
  60. GRB 050717: Refined XRT analysis.
  61. GRB050712: optical limits
  62. GRB050717: Swift XRT position
  63. Swift detection of GRB 050717
  64. GRB 050716 - UKIRT identification of candidate afterglow
  65. Swift UVOT Observations of GRB 050716
  66. GRB 050716: Refined XRT analysis.
  67. GRB050716: Refined analysis of the Swift-BAT burst
  68. GRB050716, optical observation
  69. GRB050716: Faulkes North Telescope observation
  70. GRB050716: Correction to sign in XRT coordinate
  71. Swift/BAT detection of GRB 050716
  72. GRB050715: Refined analysis of the Swift-BAT burst
  73. GRB 050715: Swift-BAT detection
  74. Swift UVOT Observations of GRB 050714B
  75. Konus-Wind observation of GRB 050713A
  76. GRB 050714B: refined XRT analysis
  77. GRB050714B: Refined analysis of the Swift-BAT burst
  78. Swift detection of a long transient (GRB 050714B?)
  79. GRB 050714: Swift XRT afterglow position
  80. GRB 050713A: XRT refined analysis
  81. GRB 050713A: RAPTOR detection of early optical emission
  82. GRB050713B :Swift/UVOT observations
  83. GRB050713b: XRT refined analysis
  84. GRB 050713B: Swift-BAT Refined Analysis
  85. Swift-BAT Trigger 145729 is not a GRB
  86. GRB 050713A: Swift/UVOT observation
  87. GRB 050713A : Swift-BAT Refined Analysis
  88. GRB050712: Swift UVOT Observation of Afterglow Emission
  89. GRB 050713A XMM-Newton observation
  90. GRB050713B: Faulkes North Telescope observation
  91. RBO RI observations of GRB 050713A
  92. GRB 050713B
  93. GRB050713: Liverpool Telescope prompt observations
  94. GRB050709: Candidate X-ray Afterglow from Chandra
  95. GRB 050713, R-band observations at NOT
  96. GRB 050713: Swift detection of Bright Burst
  97. GRB 050713A: ROTSE-III Optical Limits
  98. GRB050712: XRT refined analysis
  99. GRB 050709: Swift UVOT and XRT observations
  100. GRB 050712: Swift-BAT Refined Analysis

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