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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"

18633 results found.

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

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