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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"

19185 results found.

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

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