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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

18671 results found.

  1. GRB 050922B: Correction to BAT refined analysis, longer burst
  2. GRB050922B: refined XRT analysis
  3. Konus-Wind observation of GRB 050922C
  4. GRB050922B: Swift UVOT early upper limits.
  5. GRB 050922B: optical limit
  6. GRB 050922C: Swift XRT refined analysis
  7. HETE Fregate observations of GRB 050922C
  8. GRB 050922C: Swift-BAT refined analysis
  9. GRB 050922B: Swift-BAT refined analysis
  10. GRB050922C: optical observations
  11. GRB 050922C: Absorption redshift from the Nordic Optical Telescope
  12. GRB 050922C: optical obserations
  13. GRB 050922C: NOT optical observations
  14. GRB 050922A: Analysis of Swift/XRT TOO observation
  15. GRB 050922C: Swift detection of a bright burst
  16. GRB 050922C: ROTSE-IIId Refined Analysis
  17. GRB 050922C: ROTSE-III Detection of Possible Counterpart
  18. GRB 050922B: ROTSE-III Optical Limits
  19. GRB 050922B,optical observation
  20. GRB050922B: Swift-BAT detection of a weak long burst
  21. GRB050918: Possible Swift/XRT detected afterglow
  22. GRB050820B: analysis of the XMM-Newton observation
  23. GRB050916: Swift/UVOT Upper Limits
  24. GRB 050916: Swift-BAT refined analysis
  25. Swift-BAT trigger 155764 is not a GRB
  26. Swift-BAT trigger 155764 is probably not a GRB
  27. Swift trigger 155764: bad XRT centroid
  28. Swift-BAT trigger 155535 is definitely not a GRB
  29. GRB050916 : Swift-XRT refined analysis
  30. GRB 050916: XRT position
  31. GRB 050915B: Swift-BAT refined analysis
  32. GRB 050915B: Swift/UVOT Upper Limits
  33. GRB050916: Swift-BAT detection of a long weak burst
  34. GRB 050915B: XRT position
  35. GRB050915B: Swift-BAT detection of a long bright burst
  36. GRB050915: Swift/UVOT upper limits
  37. GRB 050915: KAIT optical limit
  38. GRB 050915: IR Observations
  39. GRB 050915: Swift XRT refined analysis
  40. GRB 050915: Swift-BAT refined analysis
  41. GRB050915, optical observations
  42. GRB050915: XRT position
  43. GRB 050915: ROTSE-III optical limits
  44. GRB 050915: Swift detection of a GRB
  45. GRB050911: Upper limit on X-ray afterglow
  46. Swift-BAT trigger 155072 ground analysis
  47. Swift-BAT trigger 155072 is probably not a GRB
  48. GRB050914: XRT position probably due to cosmic ray
  49. Swift is in normal operation
  50. GRB050911: Swift UVOT followup observations
  51. GRB 050911, optical content of Swift/XRT error box
  52. GRB050911: Swift-XRT position
  53. GRB 050911, optical observations
  54. GRB 050911: Swift-BAT refined analysis
  55. Later Swift-BAT triggers 154632 and 154633 RETRACTION
  56. GRB050911: Swift-BAT detection of a long burst
  57. GRB050908: detection of Swift/UVOT optical counterpart
  58. RBO GRB 050908 observations
  59. WIRO observations in I of GRB 050908
  60. GRB 050906: Possible X-ray Counterpart
  61. GRB050908: Swift/UVOT Early upper limits
  62. GRB050908 : Swift-XRT refined analysis
  63. GRB 050908: Swift-BAT refined analysis
  64. GRB 050908: Optical observations
  65. Gemini Spectroscopy of GRB 050908
  66. GRB 050908 : Swift XRT position
  67. GRB 050908: KAIT observations
  68. GRB 050908: P60 Confirmation of Optical Afterglow
  69. GRB 050908: Swift detection of a burst
  70. Swift trigger 154073 is not a GRB
  71. GRB050904: CrAO optical observations
  72. GRB 050904 BAT refined analysis of complete data set
  73. GRB 050906: MARGE Optical Limits
  74. GRB 050906: Swift-BAT refined analysis
  75. GRB 050906: Swift XRT upper limit
  76. GRB050906: P60 Observations
  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: Swift/UVOT observations
  81. GRB 050904: early Swift XRT analysis results
  82. GRB 050904: BAT refined analysis of partial data set
  83. GRB050904: P60 Observations
  84. GRB 050904: TAROT optical limits
  85. GRB050904: Swift-BAT detection of a probable burst
  86. Swift-BAT triggers 153461-153465 are not GRBs
  87. Retraction of Swift-BAT trigger #153355
  88. GRB 050824: MDM Observations
  89. GRB 050827: Swift XRT preliminary analysis results
  90. Swift Trigger #152652 is not a GRB
  91. GRB050827: Swift/UVOT upper limits
  92. GRB 050827: Optical Limit
  93. GRB 050827: XRT possible afterglow detection
  94. GRB050827: RTT150 optical observations
  95. GRB 050827: Swift-BAT refined analysis
  96. GRB050827: Swift-BAT detection of a burst
  97. GRB 050826: Optical Candidate
  98. GRB050824, HETE-2 Observation
  99. GRB 050826: Swift XRT preliminary analysis results
  100. GRB 050826: BAT refined analysis

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