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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"
  1. GRB060501: Swift UVOT followup observations
  2. GRB060502: Super-LOTIS Observations
  3. GRB 060502: P60 Afterglow Confirmation
  4. GRB 060502: Swift detection of a burst with an optical counterpart
  5. GRB 060501: MDM Observations
  6. GRB060501: Super-LOTIS observations
  7. GRB060501: P60 imaging and afterglow candidate
  8. GRB 060501: Refined analysis of the Swift-BAT burst
  9. GRB060501: Swift XRT position
  10. GRB 060501: ROTSE-III Optical Limits
  11. GRB 060501: Swift detection of a burst
  12. IPN triangulation of GRB060429 (short/hard)
  13. Konus-Wind observation of GRB 060427B
  14. GRB060428B - SDSS Pre-Burst Observations
  15. GRB060428B: optical observation
  16. GRB060428B: possible detection of an optical counterpart by Swift/UVOT.
  17. GRB 060428B: MDM Observations
  18. GRB 060428A: PROMPT Observations
  19. GRB 060427B: MASTER optical observations
  20. GRB060428B: Swift XRT Team refined analysis
  21. GRB 060427B: IPN localization of a short hard burst
  22. GRB 060428B: Refined analysis of the Swift-BAT burst
  23. GRB 060428B: Xinglong I-band limit
  24. GRB 060428B: KAIT observations
  25. GRB060425:MASTER optical limit
  26. GRB 051117A: Bright host galaxy not confirmed
  27. GRB060428A: Swift/UVOT observations.
  28. GRB060428B, optical observation
  29. GRB 060428A: Refined analysis of the Swift-BAT burst
  30. GRB 060428b : Kiso R-band limit
  31. GRB060427:MASTER optical limit
  32. GRB 060428b: Optical afterglow candidate
  33. GRB060428A: Swift XRT Team refined analysis
  34. GRB 060428B: Swift detection of a burst
  35. GRB 060427: NIR observations
  36. GRB060427: Xinglong optical Observations
  37. GRB 060428: Swift detection of a burst
  38. GRB 060427: NOT observations
  39. GRB 060427: Swift/UVOT upper limits.
  40. GRB 060427: Refined analysis of the Swift-BAT burst
  41. GRB060427: Swift XRT Team refined analysis
  42. GRB060418: Swift XRT Team Further Refined Analysis
  43. GRB060425:MASTER survey observations
  44. GRB 060427, optical observation
  45. GRB 060427: Swift detection of a burst
  46. GRB 060425: IPN localization and KW spectrum of a short, hard burst
  47. An interactive program for GRB pseudo-redshift computations
  48. GRB060424: optical afterglow detection
  49. GRB060418: Further Analysis of MIKE Spectroscopy
  50. GRB 060424: Refined analysis of the Swift-BAT burst
  51. GRB 060424: Swift detection of a burst
  52. GRB 060421: TTT Observations
  53. OT 060420: Likely Not a New Cosmic Transient
  54. No OT 060420 in MASCOT images
  55. Swift-BAT detection of Mrk 421
  56. OT 060420: CONCAM detection of a candidate new magnitude 5 optical
  57. GRB060421: Swift/UVOT observations
  58. GRB 060421: Swift-BAT Refined Analysis
  59. GRB 060421: Swift-XRT refined analysis
  60. GRB 060418: prediction of t_break
  61. GRB060418: optical observations
  62. Konus-Wind observation of GRB 060418
  63. GRB(?)060421:MASTER optical limit
  64. GRB(?)060421 : XRT position
  65. Possible GRB060421: BART limits
  66. GRB(?) 060421: Swift detection of a burst
  67. Erratum of GCN 4983 for GRB 060418 IR follow-up
  68. GRB 060418 : IR afterglow observations
  69. GRB 060418 : Lulin Optical follow-up
  70. GRB 060418: JHKs PAIRITEL Observations of Afterglow
  71. GRB 060418: Radio Observations
  72. GRB060418, BVRcIc field calibration
  73. GRB060418: Swift/UVOT Observations
  74. GRB060418: Optical Observations
  75. GRB 060418: FRAM early afterglow observation
  76. GRB 060418: Refined Analysis of the Swift-BAT burst
  77. VLT/UVES observations of GRB060418
  78. GRB060418: Swift XRT Team Refined Analysis
  79. GRB 060418, SMARTS continuing afterglow observations
  80. GRB 060418: PROMPT Detections
  81. GRB 060418, SMARTS optical/IR afterglow observations
  82. GRB060418: Magellan/MIKE Spectroscopic Redshift
  83. GRB060418 : LT optical afterglow observation
  84. GRB 060418: REM candidate afterglow
  85. GRB 060418: Swift detection of a burst with bright x-ray and optical afterglow
  86. SGR 1900+14: Refined analysis of the Swift-BAT outburst
  87. GRB060413: Swift/UVOT upper limits
  88. GRB 060413: REM NIR Observations
  89. SGR 1900+14: Swift detection of an outburst
  90. GRB 060413: Refined analysis of the Swift-BAT burst
  91. GRB 060413: Watcher UBVR observations
  92. GRB 060413: XRT refined analysis
  93. GRB 060413: No Optical Afterglow in Swift/UVOT TDRSS Data
  94. GRB 060413: Swift detection of a burst
  95. GRB060403: optical observations
  96. GRB 060403 Optical observations
  97. GRB 060403: MITSuME optical observation
  98. GRB060403: Optical Limit
  99. GRB060403: XRT refined analysis
  100. GRB 060403: Swift/UVOT upper limits

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