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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"

19538 results found.

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

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