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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.

Advanced Search Examples (click to copy):

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

19532 results found.

  1. GRB051022: Swift XRT Position
  2. GRB051021: Swift/UVOT Upper Limits
  3. GRB 051021B: Refined analysis of the Swift-BAT burst
  4. GRB051021B: Swift XRT Position
  5. GRB 051021B: Swift detection of a burst
  6. GRB051021: Swift XRT analysis
  7. GRB051021.63
  8. Swift-BAT trigger 160640 is not a real GRB
  9. Swift-BAT trigger 160619 is not a GRB
  10. Swift-BAT triggered on a posible CR Shower or possible GRB
  11. GRB 051016A: Swift/UVOT upper limits
  12. GRB 051016B: refined analysis of the Swift/XRT data
  13. GRB 051016B: Swift/UVOT detection
  14. GRB 051016B : Optical follow-up at Lulin
  15. GRB 051016B: Refined analysis of the Swift-BAT burst
  16. GRB 051016B: Swift detection of a soft burst
  17. GRB 051016: Swift-BAT refined analysis
  18. GRB051016 XMM-Newton observation
  19. GRB051016: Swift XRT refined analysis.
  20. GRB051016: Swift detection of a burst
  21. Photometric calibration of Swift/UVOT and Re-analysis of Swift/UVOT GRB 050922C data
  22. GRB 051012: Swift-BAT detection of burst yesterday
  23. Swift trigger 159578 is not a burst
  24. Swift-BAT Trigger 159578 is a possible burst
  25. GRB050805A: Rc optical observations
  26. GRB 051006: Swift/UVOT Upper Limits
  27. GRB 051008 - a low redshift low-luminosity burst?
  28. GRB051008: Swift XRT refined analysis
  29. GRB051008 - Swift UVOT upper limits
  30. Konus-Wind observation of GRB 051008
  31. GRB051008: Final refined analysis of the Swift-BAT burst
  32. GRB 051008: R-band upper limit
  33. GRB051008: Refined analysis of the Swift-BAT burst
  34. GRB 051008: Swift XRT position
  35. GRB 051008: early Swift XRT analysis
  36. GRB 051008: Swift UVOT Candidate
  37. GRB051008: Swift-BAT detection of a bright burst
  38. GRB 051006: XRT refined analysis
  39. Swift-BAT trigger 158700 is a probable Cosmic Ray Shower Event
  40. GRB 051006: optical observations at Sierra Nevada
  41. GRB051006: Refined analysis of the Swift-BAT burst
  42. GRB 051006: XRT position
  43. GRB051006: Swift detection of a burst
  44. Swift-BAT triggers 158261 and 158262 Retraction
  45. GRB051001: Swift UVOT Upper Limits
  46. GRB 050925: Second Epoch WSRT Radio Observations
  47. GRB 051001: Swift XRT refined analysis
  48. GRB 051001, optical observations at Mt. John
  49. GRB 051001: I-band limit
  50. GRB 051001: Swift-BAT refined analysis
  51. GRB 051001: Swift Detection of a Burst
  52. GRB 051001: ROTSE-III Optical Limits
  53. GRB050922B: optical limit
  54. GRB050925: Swift/XRT limits
  55. GRB/SGR 050925: IR Observations
  56. GRB050922C - Swift UVOT preliminary analysis
  57. GRB 050925: WSRT Radio Observations
  58. GRB050925: Swift UVOT upper limits
  59. Refined analysis of the Swift-BAT soft short burst
  60. GRB050925: Faulkes Telescope North R-band limit
  61. GRB050925: Swift-BAT detection of a short burst
  62. GRB 050922B: Correction to BAT refined analysis, longer burst
  63. GRB050922B: refined XRT analysis
  64. Konus-Wind observation of GRB 050922C
  65. GRB050922B: Swift UVOT early upper limits.
  66. GRB 050922B: optical limit
  67. GRB 050922C: Swift XRT refined analysis
  68. HETE Fregate observations of GRB 050922C
  69. GRB 050922C: Swift-BAT refined analysis
  70. GRB 050922B: Swift-BAT refined analysis
  71. GRB050922C: optical observations
  72. GRB 050922C: Absorption redshift from the Nordic Optical Telescope
  73. GRB 050922C: optical obserations
  74. GRB 050922C: NOT optical observations
  75. GRB 050922A: Analysis of Swift/XRT TOO observation
  76. GRB 050922C: Swift detection of a bright burst
  77. GRB 050922C: ROTSE-IIId Refined Analysis
  78. GRB 050922C: ROTSE-III Detection of Possible Counterpart
  79. GRB 050922B: ROTSE-III Optical Limits
  80. GRB 050922B,optical observation
  81. GRB050922B: Swift-BAT detection of a weak long burst
  82. GRB050918: Possible Swift/XRT detected afterglow
  83. GRB050820B: analysis of the XMM-Newton observation
  84. GRB050916: Swift/UVOT Upper Limits
  85. GRB 050916: Swift-BAT refined analysis
  86. Swift-BAT trigger 155764 is not a GRB
  87. Swift-BAT trigger 155764 is probably not a GRB
  88. Swift trigger 155764: bad XRT centroid
  89. Swift-BAT trigger 155535 is definitely not a GRB
  90. GRB050916 : Swift-XRT refined analysis
  91. GRB 050916: XRT position
  92. GRB 050915B: Swift-BAT refined analysis
  93. GRB 050915B: Swift/UVOT Upper Limits
  94. GRB050916: Swift-BAT detection of a long weak burst
  95. GRB 050915B: XRT position
  96. GRB050915B: Swift-BAT detection of a long bright burst
  97. GRB050915: Swift/UVOT upper limits
  98. GRB 050915: KAIT optical limit
  99. GRB 050915: IR Observations
  100. GRB 050915: Swift XRT refined analysis

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