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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"

18635 results found.

  1. GRB051021A: Swift XRT refined analysis
  2. GRB051022: Optical Observations
  3. GRB 051022, J & K-band observation
  4. GRB051022: Swift XRT Position
  5. GRB051021: Swift/UVOT Upper Limits
  6. GRB 051021B: Refined analysis of the Swift-BAT burst
  7. GRB051021B: Swift XRT Position
  8. GRB 051021B: Swift detection of a burst
  9. GRB051021: Swift XRT analysis
  10. GRB051021.63
  11. Swift-BAT trigger 160640 is not a real GRB
  12. Swift-BAT trigger 160619 is not a GRB
  13. Swift-BAT triggered on a posible CR Shower or possible GRB
  14. GRB 051016A: Swift/UVOT upper limits
  15. GRB 051016B: refined analysis of the Swift/XRT data
  16. GRB 051016B: Swift/UVOT detection
  17. GRB 051016B : Optical follow-up at Lulin
  18. GRB 051016B: Refined analysis of the Swift-BAT burst
  19. GRB 051016B: Swift detection of a soft burst
  20. GRB 051016: Swift-BAT refined analysis
  21. GRB051016 XMM-Newton observation
  22. GRB051016: Swift XRT refined analysis.
  23. GRB051016: Swift detection of a burst
  24. Photometric calibration of Swift/UVOT and Re-analysis of Swift/UVOT GRB 050922C data
  25. GRB 051012: Swift-BAT detection of burst yesterday
  26. Swift trigger 159578 is not a burst
  27. Swift-BAT Trigger 159578 is a possible burst
  28. GRB050805A: Rc optical observations
  29. GRB 051006: Swift/UVOT Upper Limits
  30. GRB 051008 - a low redshift low-luminosity burst?
  31. GRB051008: Swift XRT refined analysis
  32. GRB051008 - Swift UVOT upper limits
  33. Konus-Wind observation of GRB 051008
  34. GRB051008: Final refined analysis of the Swift-BAT burst
  35. GRB 051008: R-band upper limit
  36. GRB051008: Refined analysis of the Swift-BAT burst
  37. GRB 051008: Swift XRT position
  38. GRB 051008: early Swift XRT analysis
  39. GRB 051008: Swift UVOT Candidate
  40. GRB051008: Swift-BAT detection of a bright burst
  41. GRB 051006: XRT refined analysis
  42. Swift-BAT trigger 158700 is a probable Cosmic Ray Shower Event
  43. GRB 051006: optical observations at Sierra Nevada
  44. GRB051006: Refined analysis of the Swift-BAT burst
  45. GRB 051006: XRT position
  46. GRB051006: Swift detection of a burst
  47. Swift-BAT triggers 158261 and 158262 Retraction
  48. GRB051001: Swift UVOT Upper Limits
  49. GRB 050925: Second Epoch WSRT Radio Observations
  50. GRB 051001: Swift XRT refined analysis
  51. GRB 051001, optical observations at Mt. John
  52. GRB 051001: I-band limit
  53. GRB 051001: Swift-BAT refined analysis
  54. GRB 051001: Swift Detection of a Burst
  55. GRB 051001: ROTSE-III Optical Limits
  56. GRB050922B: optical limit
  57. GRB050925: Swift/XRT limits
  58. GRB/SGR 050925: IR Observations
  59. GRB050922C - Swift UVOT preliminary analysis
  60. GRB 050925: WSRT Radio Observations
  61. GRB050925: Swift UVOT upper limits
  62. Refined analysis of the Swift-BAT soft short burst
  63. GRB050925: Faulkes Telescope North R-band limit
  64. GRB050925: Swift-BAT detection of a short burst
  65. GRB 050922B: Correction to BAT refined analysis, longer burst
  66. GRB050922B: refined XRT analysis
  67. Konus-Wind observation of GRB 050922C
  68. GRB050922B: Swift UVOT early upper limits.
  69. GRB 050922B: optical limit
  70. GRB 050922C: Swift XRT refined analysis
  71. HETE Fregate observations of GRB 050922C
  72. GRB 050922C: Swift-BAT refined analysis
  73. GRB 050922B: Swift-BAT refined analysis
  74. GRB050922C: optical observations
  75. GRB 050922C: Absorption redshift from the Nordic Optical Telescope
  76. GRB 050922C: optical obserations
  77. GRB 050922C: NOT optical observations
  78. GRB 050922A: Analysis of Swift/XRT TOO observation
  79. GRB 050922C: Swift detection of a bright burst
  80. GRB 050922C: ROTSE-IIId Refined Analysis
  81. GRB 050922C: ROTSE-III Detection of Possible Counterpart
  82. GRB 050922B: ROTSE-III Optical Limits
  83. GRB 050922B,optical observation
  84. GRB050922B: Swift-BAT detection of a weak long burst
  85. GRB050918: Possible Swift/XRT detected afterglow
  86. GRB050820B: analysis of the XMM-Newton observation
  87. GRB050916: Swift/UVOT Upper Limits
  88. GRB 050916: Swift-BAT refined analysis
  89. Swift-BAT trigger 155764 is not a GRB
  90. Swift-BAT trigger 155764 is probably not a GRB
  91. Swift trigger 155764: bad XRT centroid
  92. Swift-BAT trigger 155535 is definitely not a GRB
  93. GRB050916 : Swift-XRT refined analysis
  94. GRB 050916: XRT position
  95. GRB 050915B: Swift-BAT refined analysis
  96. GRB 050915B: Swift/UVOT Upper Limits
  97. GRB050916: Swift-BAT detection of a long weak burst
  98. GRB 050915B: XRT position
  99. GRB050915B: Swift-BAT detection of a long bright burst
  100. GRB050915: Swift/UVOT upper limits

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