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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"

18539 results found.

  1. GRB 050721A: Swift-BAT refined analysis
  2. GRB 050721A: Early Swift XRT analysis results
  3. Swift BAT Trigger 146986 is SWIFT J1753.5-0127
  4. GRB 050721a: Optical Observations
  5. GRB050721A: Swift-BAT detection of a weak burst
  6. GRB 050714a: Refined XRT analysis and afterglow confirmation
  7. Swift-BAT trigger 146731 is not a real GRB
  8. Swift-BAT detection of a possible GRB
  9. GRB050717
  10. Konus-Wind observation of GRB 050717
  11. Swift/UVOT Observations of GRB 050717
  12. GRB 050717: Swift-BAT refined analysis
  13. GRB 050717: Refined XRT analysis.
  14. GRB050712: optical limits
  15. GRB050717: Swift XRT position
  16. Swift detection of GRB 050717
  17. GRB 050716 - UKIRT identification of candidate afterglow
  18. Swift UVOT Observations of GRB 050716
  19. GRB 050716: Refined XRT analysis.
  20. GRB050716: Refined analysis of the Swift-BAT burst
  21. GRB050716, optical observation
  22. GRB050716: Faulkes North Telescope observation
  23. GRB050716: Correction to sign in XRT coordinate
  24. Swift/BAT detection of GRB 050716
  25. GRB050715: Refined analysis of the Swift-BAT burst
  26. GRB 050715: Swift-BAT detection
  27. Swift UVOT Observations of GRB 050714B
  28. Konus-Wind observation of GRB 050713A
  29. GRB 050714B: refined XRT analysis
  30. GRB050714B: Refined analysis of the Swift-BAT burst
  31. Swift detection of a long transient (GRB 050714B?)
  32. GRB 050714: Swift XRT afterglow position
  33. GRB 050713A: XRT refined analysis
  34. GRB 050713A: RAPTOR detection of early optical emission
  35. GRB050713B :Swift/UVOT observations
  36. GRB050713b: XRT refined analysis
  37. GRB 050713B: Swift-BAT Refined Analysis
  38. Swift-BAT Trigger 145729 is not a GRB
  39. GRB 050713A: Swift/UVOT observation
  40. GRB 050713A : Swift-BAT Refined Analysis
  41. GRB050712: Swift UVOT Observation of Afterglow Emission
  42. GRB 050713A XMM-Newton observation
  43. GRB050713B: Faulkes North Telescope observation
  44. RBO RI observations of GRB 050713A
  45. GRB 050713B
  46. GRB050713: Liverpool Telescope prompt observations
  47. GRB050709: Candidate X-ray Afterglow from Chandra
  48. GRB 050713, R-band observations at NOT
  49. GRB 050713: Swift detection of Bright Burst
  50. GRB 050713A: ROTSE-III Optical Limits
  51. GRB050712: XRT refined analysis
  52. GRB 050709: Swift UVOT and XRT observations
  53. GRB 050712: Swift-BAT Refined Analysis
  54. GRB050712: UVOT candidate optical counterpart
  55. GRB 050712: Swift XRT afterglow position
  56. GRB 050712: Swift detection of a weak burst
  57. GRB 050525a: ARC 3.5-meter Optical and NIR Observations
  58. GRB 050626: Swift XRT observations
  59. GRB 050701
  60. GRB 050701, optical observations
  61. GRB 050701: Refined XRT analysis
  62. Swift UVOT observations of GRB 050701
  63. GRB050701: Swift-BAT Refined analysis
  64. GRB 050701: Swift XRT afterglow position
  65. Swift trigger 143708 is really GRB 050701
  66. GRB 050525A: Swift Late-Time Decay Rate
  67. CORRECTION: GRB050603 Swift UVOT Afterglow Observations
  68. GRB 050416(a): Host Galaxy Redshift Determination
  69. Swift/UVOT observations of GRB050607
  70. GRB 050607: RAPTOR-S Early Optical Limits
  71. GRB050607: KAIT optical limits
  72. GRB 050607: MDM Observations
  73. GRB050607,optical observation
  74. GRB 050607 - XRT refined data analysis
  75. GRB050607 optical limit by "Pi of the Sky"
  76. GRB050607: Swift Detection of a long GRB
  77. GRB 050603 - XRT data analysis of the first day
  78. Konus-Wind observation of GRB 050603
  79. GRB 050603: Analysis of UVOT data
  80. GRB050603: Fading Afterglow observed by Swift UVOT
  81. GRB 050603: Swift XRT Position
  82. GRB 050603: Swift-BAT refined analysis of a long three-spiked burst
  83. Swift/BAT Detection of GRB050603
  84. GRB 050408: jet break in the XRT light curve
  85. GRB050528, XRT observations
  86. Correction to GCN Circ 3502 on GRB 050528
  87. Swift-BAT GRB 050528: a soft burst
  88. Update on Swift-BAT GRB 050528 (Trigger 130679)
  89. Possible GRB050528: no candidate from Liverpool Telescope
  90. Swift-BAT detection of possible GRB 050528
  91. GRB 050509b: refined XRT/Chandra afterglow position analysis
  92. GRB050525a: optical upper limits
  93. GRB 050525B: Swift-BAT observations
  94. GRB050525A,optical observation
  95. GRB050525: Super-LOTIS observations
  96. GRB 050525, spectral lag pseudo-redshift
  97. GRB050306: optical afterglow not confirmed
  98. GRB 050525A: BOOTES simultaneous optical observations
  99. GRB 050525A: Swift-BAT refined analysis
  100. Swift/UVOT UV and optical detections of GRB 050525

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