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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"

18672 results found.

  1. IPN triangulation and Konus spectrum of the short/soft GRB051107 (large
  2. GRB051109B: no UVOT source detected
  3. GRB051109B: XRT refined analysis
  4. GRB 051109B : Lulin Optical Observations
  5. GRB051109A: further steepening in the X-ray light curve
  6. GRB051109A: XRT refined analysis
  7. GRB051109B: XRT position
  8. GRB 051109B: Super-LOTIS Observations
  9. GRB 051109B Kiso optical follow-up observation
  10. GRB 051109B: Swift detection of a burst
  11. GRB051109: Early Super-LOTIS Detection
  12. GRB 051109: Swift-BAT refined analysis
  13. GRB 051109a: MDM Observations
  14. GRB 051109A: ROTSE-III Decline rate for Optical Counterpart
  15. GRB051109: Swift detection of a burst
  16. GRB 051109a: IR Detections
  17. GRB 051109: ROTSE-III Detection of Possible Counterpart
  18. GRB051105B: Swift/XRT upper limit
  19. GRB051105B: Swift/UVOT upper limit
  20. GRB051028: Swift-XRT refined analysis
  21. GRB 051105a: MDM Observations
  22. GRB051105A: Swift/UVOT Observations
  23. IPN triangulation and Konus spectrum of the bright short/hard GRB051103
  24. XRT observations of GRB 051105A
  25. GRB 051105: Swift-BAT improved refined analysis
  26. GRB 051105: Swift-BAT refined analysis
  27. GRB 051105: Swift detection of a short burst
  28. GRB051028: Swift/UVOT upper limits
  29. GRB051028: Swift XRT Position
  30. GRB 051022: XRT Refined Spectral and Temporal Analysis--Correction
  31. GRB051022: Swift XRT measurement of jet break
  32. GRB051021B: Swift/UVOT Upper limits
  33. GRB 051022: XRT Refined Spectral and Temporal Analysis
  34. GRB051012: Swift-XRT analysis
  35. GRB051021B: Swift XRT refined analysis
  36. GRB 051022: WSRT Radio Detection
  37. GRB 051022: Swift/UVOT Upper Limits
  38. GRB051021A: Swift XRT refined analysis
  39. GRB051022: Optical Observations
  40. GRB 051022, J & K-band observation
  41. GRB051022: Swift XRT Position
  42. GRB051021: Swift/UVOT Upper Limits
  43. GRB 051021B: Refined analysis of the Swift-BAT burst
  44. GRB051021B: Swift XRT Position
  45. GRB 051021B: Swift detection of a burst
  46. GRB051021: Swift XRT analysis
  47. GRB051021.63
  48. Swift-BAT trigger 160640 is not a real GRB
  49. Swift-BAT trigger 160619 is not a GRB
  50. Swift-BAT triggered on a posible CR Shower or possible GRB
  51. GRB 051016A: Swift/UVOT upper limits
  52. GRB 051016B: refined analysis of the Swift/XRT data
  53. GRB 051016B: Swift/UVOT detection
  54. GRB 051016B : Optical follow-up at Lulin
  55. GRB 051016B: Refined analysis of the Swift-BAT burst
  56. GRB 051016B: Swift detection of a soft burst
  57. GRB 051016: Swift-BAT refined analysis
  58. GRB051016 XMM-Newton observation
  59. GRB051016: Swift XRT refined analysis.
  60. GRB051016: Swift detection of a burst
  61. Photometric calibration of Swift/UVOT and Re-analysis of Swift/UVOT GRB 050922C data
  62. GRB 051012: Swift-BAT detection of burst yesterday
  63. Swift trigger 159578 is not a burst
  64. Swift-BAT Trigger 159578 is a possible burst
  65. GRB050805A: Rc optical observations
  66. GRB 051006: Swift/UVOT Upper Limits
  67. GRB 051008 - a low redshift low-luminosity burst?
  68. GRB051008: Swift XRT refined analysis
  69. GRB051008 - Swift UVOT upper limits
  70. Konus-Wind observation of GRB 051008
  71. GRB051008: Final refined analysis of the Swift-BAT burst
  72. GRB 051008: R-band upper limit
  73. GRB051008: Refined analysis of the Swift-BAT burst
  74. GRB 051008: Swift XRT position
  75. GRB 051008: early Swift XRT analysis
  76. GRB 051008: Swift UVOT Candidate
  77. GRB051008: Swift-BAT detection of a bright burst
  78. GRB 051006: XRT refined analysis
  79. Swift-BAT trigger 158700 is a probable Cosmic Ray Shower Event
  80. GRB 051006: optical observations at Sierra Nevada
  81. GRB051006: Refined analysis of the Swift-BAT burst
  82. GRB 051006: XRT position
  83. GRB051006: Swift detection of a burst
  84. Swift-BAT triggers 158261 and 158262 Retraction
  85. GRB051001: Swift UVOT Upper Limits
  86. GRB 050925: Second Epoch WSRT Radio Observations
  87. GRB 051001: Swift XRT refined analysis
  88. GRB 051001, optical observations at Mt. John
  89. GRB 051001: I-band limit
  90. GRB 051001: Swift-BAT refined analysis
  91. GRB 051001: Swift Detection of a Burst
  92. GRB 051001: ROTSE-III Optical Limits
  93. GRB050922B: optical limit
  94. GRB050925: Swift/XRT limits
  95. GRB/SGR 050925: IR Observations
  96. GRB050922C - Swift UVOT preliminary analysis
  97. GRB 050925: WSRT Radio Observations
  98. GRB050925: Swift UVOT upper limits
  99. Refined analysis of the Swift-BAT soft short burst
  100. GRB050925: Faulkes Telescope North R-band limit

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