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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"

42276 results found.

  1. GRB 060427B: MASTER optical observations
  2. GRB060428B: Swift XRT Team refined analysis
  3. GRB 060427B: IPN localization of a short hard burst
  4. GRB 060428B: Refined analysis of the Swift-BAT burst
  5. GRB 060428B: Xinglong I-band limit
  6. GRB 060428B: KAIT observations
  7. GRB060425:MASTER optical limit
  8. GRB 051117A: Bright host galaxy not confirmed
  9. GRB060428A: Swift/UVOT observations.
  10. GRB060428B, optical observation
  11. GRB 060428A: Refined analysis of the Swift-BAT burst
  12. GRB060427:MASTER optical limit
  13. GRB 060428b: Optical afterglow candidate
  14. GRB060428A: Swift XRT Team refined analysis
  15. GRB 060428B: Swift detection of a burst
  16. GRB 060427: NIR observations
  17. GRB060427: Xinglong optical Observations
  18. GRB 060428: Swift detection of a burst
  19. GRB 060427: NOT observations
  20. GRB 060427: Swift/UVOT upper limits.
  21. GRB060427: Swift XRT Team refined analysis
  22. GRB060418: Swift XRT Team Further Refined Analysis
  23. GRB 060427, optical observation
  24. GRB 060427: Swift detection of a burst
  25. GRB 060425: IPN localization and KW spectrum of a short, hard burst
  26. An interactive program for GRB pseudo-redshift computations
  27. GRB060424: optical afterglow detection
  28. GRB060418: Further Analysis of MIKE Spectroscopy
  29. GRB 060424: Refined analysis of the Swift-BAT burst
  30. GRB 060424: Swift detection of a burst
  31. GRB 060421: TTT Observations
  32. OT 060420: Likely Not a New Cosmic Transient
  33. No OT 060420 in MASCOT images
  34. Swift-BAT detection of Mrk 421
  35. OT 060420: CONCAM detection of a candidate new magnitude 5 optical
  36. GRB060421: Swift/UVOT observations
  37. GRB 060421: Swift-XRT refined analysis
  38. GRB 060418: prediction of t_break
  39. GRB060418: optical observations
  40. Konus-Wind observation of GRB 060418
  41. GRB(?)060421:MASTER optical limit
  42. GRB(?)060421 : XRT position
  43. Possible GRB060421: BART limits
  44. GRB(?) 060421: Swift detection of a burst
  45. Erratum of GCN 4983 for GRB 060418 IR follow-up
  46. GRB 060418 : IR afterglow observations
  47. GRB 060418 : Lulin Optical follow-up
  48. GRB 060418: JHKs PAIRITEL Observations of Afterglow
  49. GRB 060418: Radio Observations
  50. GRB060418, BVRcIc field calibration
  51. GRB060418: Swift/UVOT Observations
  52. GRB060418: Optical Observations
  53. GRB 060418: FRAM early afterglow observation
  54. GRB 060418: Refined Analysis of the Swift-BAT burst
  55. VLT/UVES observations of GRB060418
  56. GRB060418: Swift XRT Team Refined Analysis
  57. GRB 060418: PROMPT Detections
  58. GRB 060418, SMARTS optical/IR afterglow observations
  59. GRB060418: Magellan/MIKE Spectroscopic Redshift
  60. GRB060418 : LT optical afterglow observation
  61. GRB 060418: REM candidate afterglow
  62. GRB 060418: Swift detection of a burst with bright x-ray and optical afterglow
  63. SGR 1900+14: Refined analysis of the Swift-BAT outburst
  64. GRB 060413: REM NIR Observations
  65. SGR 1900+14: Swift detection of an outburst
  66. GRB 060413: XRT refined analysis
  67. GRB 060413: No Optical Afterglow in Swift/UVOT TDRSS Data
  68. GRB 060413: Swift detection of a burst
  69. GRB060403: optical observations
  70. GRB 060403 Optical observations
  71. GRB 060403: MITSuME optical observation
  72. GRB060403: Optical Limit
  73. GRB060403: XRT refined analysis
  74. GRB 060403: Swift/UVOT upper limits
  75. HETE Triggers H4043 and H4044 Not Due to New Cosmic Source
  76. SGR 1900+14: BAT observations
  77. GRB060403: Swift XRT refined position
  78. Konus-Wind observation of the recent SGR 1900+14 activity. Will
  79. GRB 060403: Swift detection of a burst
  80. HETE trigger H4044: RTT150 optical observations
  81. H4044, a Repeat Outburst From The Source of H4043 (="GRB060331")
  82. Swift XRT observations of the HETE transient H4043
  83. HETE Trigger 4043: ROTSE-III Optical Limits
  84. Correction to Circular 4938, =H4043, an unusual high energy transient observed by HETE
  85. H4043, an unusual high-energy transient observed by HETE
  86. GRB 060322: LNA optical limit
  87. SGR 1900+14: bright burst detected by Konus-Wind on March 28
  88. SGR 1900+14: Swift-BAT detection of a cluster of outbursts
  89. SGR 1900+14: Swift-BAT detection of a bright outburst
  90. GRB 060218SN 2006aj: optical observations at Rozhen Observatory
  91. GRB 060323 : WIDGET simultaneous optical observations
  92. GRB 060323: Early optical observation at Xinglong
  93. GRB060218, optical observations
  94. GRB 060322: Confirmation of Swift XRT afterglow
  95. GRB 060211A: optical observation
  96. GRB060323: optical limit
  97. GRB060211B: optical observation
  98. SGR 1900+14: Refined Swift-BAT analysis of the renewed activity
  99. SGR 1900+14: Swift detection of renewed activity
  100. GRB060323: NOT optical observations

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