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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"

37764 results found.

  1. GRB050922C: UVES/VLT high resolution spectroscopy
  2. GRB050925: Swift/XRT limits
  3. GRB/SGR 050925: IR Observations
  4. GRB 050922C: break in the lightcurve
  5. GRB 050925: WSRT Radio Observations
  6. GRB 050925 : I-band observation at Xinglong observatory
  7. GRB050925: Faulkes Telescope North R-band limit
  8. GRB050925: Swift-BAT detection of a short burst
  9. GRB 050922B: Correction to BAT refined analysis, longer burst
  10. GRB050922C: TNG spectroscopic observations
  11. GRB050922B: refined XRT analysis
  12. Konus-Wind observation of GRB 050922C
  13. GRB 050922C: Refined redshift
  14. GRB OT observation
  15. GRB050922C: observation at MonteBoo
  16. INT 2.5m limit for GRB050922B
  17. GRB 050922B: optical limit
  18. GRB050922C: Optical Observations
  19. GRB 050922C: Swift XRT refined analysis
  20. HETE Fregate observations of GRB 050922C
  21. GRB 050922C: Swift-BAT refined analysis
  22. GRB 050922B: Swift-BAT refined analysis
  23. GRB 050922C: Absorption redshift from the Nordic Optical Telescope
  24. GRB 050922C: optical obserations
  25. GRB 050922C: NOT optical observations
  26. GRB 050922A: Analysis of Swift/XRT TOO observation
  27. GRB 050922C: Swift detection of a bright burst
  28. GRB 050922C: ROTSE-IIId Refined Analysis
  29. GRB 050922C: ROTSE-III Detection of Possible Counterpart
  30. GRB 050922B: ROTSE-III Optical Limits
  31. GRB 050922B,optical observation
  32. GRB050922B: Swift-BAT detection of a weak long burst
  33. Possible GRB 050922 detected by INTEGRAL
  34. GRB050820B: analysis of the XMM-Newton observation
  35. GRB050916: Swift/UVOT Upper Limits
  36. GRB 050916: Swift-BAT refined analysis
  37. GRB 050918 - A long GRB detected by INTEGRAL
  38. GRB 050915a: Radio Observations
  39. Swift-BAT trigger 155764 is not a GRB
  40. Swift-BAT trigger 155764 is probably not a GRB
  41. Swift-BAT trigger 155535 is definitely not a GRB
  42. GRB 050916: XRT position
  43. GRB 050915b, SMARTS optical/IR observations of the XRT position
  44. GRB 050915B: Swift-BAT refined analysis
  45. GRB 050915B: Swift/UVOT Upper Limits
  46. GRB 050915a: IR Transient
  47. GRB 050915B: XRT position
  48. GRB 050915b, SMARTS optical/IR observations
  49. GRB 050915: KAIT optical limit
  50. GRB 050915: IR Observations
  51. GRB 050915: Swift XRT refined analysis
  52. GRB 050915: Swift-BAT refined analysis
  53. GRB050915: P60 Optical Observations
  54. GRB 050915: ROTSE-III optical limits
  55. GRB 050915: Swift detection of a GRB
  56. GRB050911: Upper limit on X-ray afterglow
  57. Swift-BAT trigger 155072 ground analysis
  58. Swift-BAT trigger 155072 is probably not a GRB
  59. GRB 050911: LCO limits on a variable source
  60. GRB 050908: DEIMOS spectrum and further analysis
  61. Swift is in normal operation
  62. GRB 050911, optical content of Swift/XRT error box
  63. GRB 050911: LCO observations
  64. GRB 050911, optical observations
  65. GRB 050911: Swift-BAT refined analysis
  66. Later Swift-BAT triggers 154632 and 154633 RETRACTION
  67. GRB 050911: z~0.16 cluster in the field
  68. GRB 050910a: TAROT early optical limits
  69. RBO GRB 050908 observations
  70. WIRO observations in I of GRB 050908
  71. GRB 050906: Possible X-ray Counterpart
  72. GRB 050906: RTT150 optical observations
  73. GRB050908: VLT R-band decay index.
  74. GRB 050908: Swift-BAT refined analysis
  75. GRB 050908: Optical observations
  76. Gemini Spectroscopy of GRB 050908
  77. GRB 050908: spectroscopic redshift
  78. GRB 050908: Prompt PROMPT Observations
  79. GRB 050908 : Swift XRT position
  80. GRB 050908: KAIT observations
  81. GRB 050908: P60 Confirmation of Optical Afterglow
  82. GRB 050908: Optical Observations
  83. GRB 050908: Swift detection of a burst
  84. Swift trigger 154073 is not a GRB
  85. GRB 050906: Optical observations at the Very Large Telescope
  86. GRB050904: CrAO optical observations
  87. GRB 050904 BAT refined analysis of complete data set
  88. GRB 050904: Subaru Optical Spectroscopy
  89. GRB 050906: MARGE Optical Limits
  90. GRB 050906: Swift-BAT refined analysis
  91. GRB 050906: Swift XRT upper limit
  92. GRB 050906: Radio Observations
  93. GRB 050904: Keck I-band Imaging
  94. GRB 050904: more VLT NIR observations
  95. GRB 050904: BOOTES early R-band observation
  96. GRB 050904: Did SWIFT/XRT see the prompt GRB emission ?
  97. GRB 050906: Bright galaxy in BAT error box
  98. GRB 050906: Swift/BAT Detection of a possible burst
  99. GRB 050904: More SOAR
  100. GRB 050904: photometric redshift

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