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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"

18779 results found.

  1. GRB051111: Swift-BAT detection of a bright burst
  2. GRB 051111A: ROTSE-III Detection of Possible Counterpart
  3. Early RAPTOR measurements of GRB 051109a - the movie.
  4. Konus-Wind observation of GRB 051109A
  5. GRB 051109B: Swift-BAT refined analysis
  6. GRB 051109B: ROTSE-III Optical Limits
  7. GRB 051109A: Swift-UVOT Observations
  8. IPN triangulation and Konus spectrum of the short/soft GRB051107 (large
  9. GRB051109B: no UVOT source detected
  10. GRB051109B: XRT refined analysis
  11. GRB 051109B : Lulin Optical Observations
  12. GRB051109A: further steepening in the X-ray light curve
  13. GRB051109A: XRT refined analysis
  14. GRB051109B: XRT position
  15. GRB 051109B: Super-LOTIS Observations
  16. GRB 051109B Kiso optical follow-up observation
  17. GRB 051109B: Swift detection of a burst
  18. GRB051109: Early Super-LOTIS Detection
  19. GRB 051109: Swift-BAT refined analysis
  20. GRB 051109a: MDM Observations
  21. GRB 051109A: ROTSE-III Decline rate for Optical Counterpart
  22. GRB051109: Swift detection of a burst
  23. GRB 051109a: IR Detections
  24. GRB 051109: ROTSE-III Detection of Possible Counterpart
  25. GRB051105B: Swift/XRT upper limit
  26. GRB051105B: Swift/UVOT upper limit
  27. GRB051028: Swift-XRT refined analysis
  28. GRB 051105a: MDM Observations
  29. GRB051105A: Swift/UVOT Observations
  30. IPN triangulation and Konus spectrum of the bright short/hard GRB051103
  31. XRT observations of GRB 051105A
  32. GRB 051105: Swift-BAT improved refined analysis
  33. GRB 051105: Swift-BAT refined analysis
  34. GRB 051105: Swift detection of a short burst
  35. GRB051028: Swift/UVOT upper limits
  36. GRB051028: Swift XRT Position
  37. GRB 051022: XRT Refined Spectral and Temporal Analysis--Correction
  38. GRB051022: Swift XRT measurement of jet break
  39. GRB051021B: Swift/UVOT Upper limits
  40. GRB 051022: XRT Refined Spectral and Temporal Analysis
  41. GRB051012: Swift-XRT analysis
  42. GRB051021B: Swift XRT refined analysis
  43. GRB 051022: WSRT Radio Detection
  44. GRB 051022: Swift/UVOT Upper Limits
  45. GRB051021A: Swift XRT refined analysis
  46. GRB051022: Optical Observations
  47. GRB 051022, J & K-band observation
  48. GRB051022: Swift XRT Position
  49. GRB051021: Swift/UVOT Upper Limits
  50. GRB 051021B: Refined analysis of the Swift-BAT burst
  51. GRB051021B: Swift XRT Position
  52. GRB 051021B: Swift detection of a burst
  53. GRB051021: Swift XRT analysis
  54. GRB051021.63
  55. Swift-BAT trigger 160640 is not a real GRB
  56. Swift-BAT trigger 160619 is not a GRB
  57. Swift-BAT triggered on a posible CR Shower or possible GRB
  58. GRB 051016A: Swift/UVOT upper limits
  59. GRB 051016B: refined analysis of the Swift/XRT data
  60. GRB 051016B: Swift/UVOT detection
  61. GRB 051016B : Optical follow-up at Lulin
  62. GRB 051016B: Refined analysis of the Swift-BAT burst
  63. GRB 051016B: Swift detection of a soft burst
  64. GRB 051016: Swift-BAT refined analysis
  65. GRB051016 XMM-Newton observation
  66. GRB051016: Swift XRT refined analysis.
  67. GRB051016: Swift detection of a burst
  68. Photometric calibration of Swift/UVOT and Re-analysis of Swift/UVOT GRB 050922C data
  69. GRB 051012: Swift-BAT detection of burst yesterday
  70. Swift trigger 159578 is not a burst
  71. Swift-BAT Trigger 159578 is a possible burst
  72. GRB050805A: Rc optical observations
  73. GRB 051006: Swift/UVOT Upper Limits
  74. GRB 051008 - a low redshift low-luminosity burst?
  75. GRB051008: Swift XRT refined analysis
  76. GRB051008 - Swift UVOT upper limits
  77. Konus-Wind observation of GRB 051008
  78. GRB051008: Final refined analysis of the Swift-BAT burst
  79. GRB 051008: R-band upper limit
  80. GRB051008: Refined analysis of the Swift-BAT burst
  81. GRB 051008: Swift XRT position
  82. GRB 051008: early Swift XRT analysis
  83. GRB 051008: Swift UVOT Candidate
  84. GRB051008: Swift-BAT detection of a bright burst
  85. GRB 051006: XRT refined analysis
  86. Swift-BAT trigger 158700 is a probable Cosmic Ray Shower Event
  87. GRB 051006: optical observations at Sierra Nevada
  88. GRB051006: Refined analysis of the Swift-BAT burst
  89. GRB 051006: XRT position
  90. GRB051006: Swift detection of a burst
  91. Swift-BAT triggers 158261 and 158262 Retraction
  92. GRB051001: Swift UVOT Upper Limits
  93. GRB 050925: Second Epoch WSRT Radio Observations
  94. GRB 051001: Swift XRT refined analysis
  95. GRB 051001, optical observations at Mt. John
  96. GRB 051001: I-band limit
  97. GRB 051001: Swift-BAT refined analysis
  98. GRB 051001: Swift Detection of a Burst
  99. GRB 051001: ROTSE-III Optical Limits
  100. GRB050922B: optical limit

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