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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"

19534 results found.

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

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