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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. GRB050916: Swift/UVOT Upper Limits
  2. GRB 050916: Swift-BAT refined analysis
  3. GRB 050918 - A long GRB detected by INTEGRAL
  4. GRB 050915a: Radio Observations
  5. Swift-BAT trigger 155764 is not a GRB
  6. Swift-BAT trigger 155764 is probably not a GRB
  7. Swift trigger 155764: bad XRT centroid
  8. Swift-BAT trigger 155535 is definitely not a GRB
  9. GRB050916 : Swift-XRT refined analysis
  10. GRB 050916: XRT position
  11. GRB 050915b, SMARTS optical/IR observations of the XRT position
  12. GRB 050915B: Swift-BAT refined analysis
  13. GRB 050915B: Swift/UVOT Upper Limits
  14. GRB050916: Swift-BAT detection of a long weak burst
  15. GRB 050915a: IR Transient
  16. GRB 050915B: XRT position
  17. GRB 050915b, SMARTS optical/IR observations
  18. GRB050915B: Swift-BAT detection of a long bright burst
  19. GRB050915: Swift/UVOT upper limits
  20. GRB 050915: KAIT optical limit
  21. GRB 050915: IR Observations
  22. GRB 050915: Swift XRT refined analysis
  23. GRB 050915: Swift-BAT refined analysis
  24. GRB050915: P60 Optical Observations
  25. GRB050915, optical observations
  26. GRB050915: XRT position
  27. GRB 050915: ROTSE-III optical limits
  28. GRB 050915: Swift detection of a GRB
  29. GRB050911: Upper limit on X-ray afterglow
  30. Swift-BAT trigger 155072 ground analysis
  31. Swift-BAT trigger 155072 is probably not a GRB
  32. GRB050914: XRT position probably due to cosmic ray
  33. GRB 050911: LCO limits on a variable source
  34. GRB 050908: DEIMOS spectrum and further analysis
  35. Swift is in normal operation
  36. GRB050911: Swift UVOT followup observations
  37. GRB 050911, optical content of Swift/XRT error box
  38. GRB050911: Swift-XRT position
  39. GRB 050911: LCO observations
  40. GRB 050911, optical observations
  41. GRB 050911: Swift-BAT refined analysis
  42. Later Swift-BAT triggers 154632 and 154633 RETRACTION
  43. GRB 050911: z~0.16 cluster in the field
  44. GRB050911: Swift-BAT detection of a long burst
  45. GRB050908: detection of Swift/UVOT optical counterpart
  46. GRB 050910a: TAROT early optical limits
  47. RBO GRB 050908 observations
  48. WIRO observations in I of GRB 050908
  49. GRB 050906: Possible X-ray Counterpart
  50. GRB 050906: RTT150 optical observations
  51. GRB050908: Swift/UVOT Early upper limits
  52. GRB050908: VLT R-band decay index.
  53. GRB050908 : Swift-XRT refined analysis
  54. GRB 050908: Swift-BAT refined analysis
  55. GRB 050908: Optical observations
  56. Gemini Spectroscopy of GRB 050908
  57. GRB 050908: spectroscopic redshift
  58. GRB 050908: Prompt PROMPT Observations
  59. GRB 050908 : Swift XRT position
  60. GRB 050908: KAIT observations
  61. GRB 050908: P60 Confirmation of Optical Afterglow
  62. GRB 050908: Optical Observations
  63. GRB 050908: Swift detection of a burst
  64. Swift trigger 154073 is not a GRB
  65. GRB 050906: Optical observations at the Very Large Telescope
  66. GRB050904: CrAO optical observations
  67. GRB 050904 BAT refined analysis of complete data set
  68. GRB 050904: Subaru Optical Spectroscopy
  69. GRB 050906: MARGE Optical Limits
  70. GRB 050906: Swift-BAT refined analysis
  71. GRB 050906: Swift XRT upper limit
  72. GRB 050906: Radio Observations
  73. GRB 050904: Keck I-band Imaging
  74. GRB050906: P60 Observations
  75. GRB 050904: more VLT NIR observations
  76. GRB 050904: BOOTES early R-band observation
  77. GRB 050904: Did SWIFT/XRT see the prompt GRB emission ?
  78. GRB 050906: Bright galaxy in BAT error box
  79. GRB 050906: Swift/BAT Detection of a possible burst
  80. GRB 050904: More SOAR
  81. GRB 050904: photometric redshift
  82. GRB 050904: Swift/UVOT observations
  83. GRB 050904: Afterglow Astrometry
  84. GRB 050904: NIR object inside the XRT error box
  85. GRB 050904: early Swift XRT analysis results
  86. GRB 050904: SOAR YJ and PROMPT Ic Observations
  87. GRB 050904: BAT refined analysis of partial data set
  88. GRB 050904: TAROT optical measurements
  89. GRB050904: Optical Observations
  90. GRB 050904: Environmental Constraints
  91. GRB 050904: Possible High-Redshift GRB
  92. GRB 050904: SOAR/PROMPT Observations
  93. GRB050904: P60 Observations
  94. GRB 050904: TAROT optical limits
  95. GRB050904: Swift-BAT detection of a probable burst
  96. Swift-BAT triggers 153461-153465 are not GRBs
  97. Retraction of Swift-BAT trigger #153355
  98. GRB 050824: MDM Observations
  99. GRB 050827: Swift XRT preliminary analysis results
  100. IBAS Alerts 2641 and 2642: not a real GRB

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