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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"

18400 results found.

  1. GRB051114: results of the Swift-XRT observation
  2. GRB 051114: Swift-BAT refined analysis
  3. GRB050925: analysis of the XMM-Newton observation
  4. GRB 051114: Swift-BAT detection of a short burst
  5. GRB 051113: Swift-BAT refined analysis
  6. GRB 051113: Swift-BAT detection of a burst
  7. GRB 051111: AEOS optical observations
  8. GRB 051109A Milagro GeV/TeV Observations
  9. GRB/SGR 050925: XMM-Newton ToO observation
  10. GRB051111: Swift/UVOT Observations
  11. GRB051111: XRT preliminary analysis
  12. GRB 051111: Swift-BAT refined analysis
  13. GRB 051109A Optical Observations
  14. GRB051111a: SARA Observations
  15. GRB 051111A: KAIT optical observations
  16. GRB051111: Super-LOTIS Early Detection
  17. GRB 051111: ROTSE-III Analysis of Prompt Counterpart
  18. Faulkes Telescope R-band detection of GRB051111
  19. GRB051111: Swift-BAT detection of a bright burst
  20. GRB 051111A: ROTSE-III Detection of Possible Counterpart
  21. Early RAPTOR measurements of GRB 051109a - the movie.
  22. Konus-Wind observation of GRB 051109A
  23. GRB 051109B: Swift-BAT refined analysis
  24. GRB 051109B: ROTSE-III Optical Limits
  25. GRB 051109A: Swift-UVOT Observations
  26. IPN triangulation and Konus spectrum of the short/soft GRB051107 (large
  27. GRB051109B: no UVOT source detected
  28. GRB051109B: XRT refined analysis
  29. GRB 051109B : Lulin Optical Observations
  30. GRB051109A: further steepening in the X-ray light curve
  31. GRB051109A: XRT refined analysis
  32. GRB051109B: XRT position
  33. GRB 051109B: Super-LOTIS Observations
  34. GRB 051109B Kiso optical follow-up observation
  35. GRB 051109B: Swift detection of a burst
  36. GRB051109: Early Super-LOTIS Detection
  37. GRB 051109: Swift-BAT refined analysis
  38. GRB 051109a: MDM Observations
  39. GRB 051109A: ROTSE-III Decline rate for Optical Counterpart
  40. GRB051109: Swift detection of a burst
  41. GRB 051109a: IR Detections
  42. GRB 051109: ROTSE-III Detection of Possible Counterpart
  43. GRB051105B: Swift/XRT upper limit
  44. GRB051105B: Swift/UVOT upper limit
  45. GRB051028: Swift-XRT refined analysis
  46. GRB 051105a: MDM Observations
  47. GRB051105A: Swift/UVOT Observations
  48. IPN triangulation and Konus spectrum of the bright short/hard GRB051103
  49. XRT observations of GRB 051105A
  50. GRB 051105: Swift-BAT improved refined analysis
  51. GRB 051105: Swift-BAT refined analysis
  52. GRB 051105: Swift detection of a short burst
  53. GRB051028: Swift/UVOT upper limits
  54. GRB051028: Swift XRT Position
  55. GRB 051022: XRT Refined Spectral and Temporal Analysis--Correction
  56. GRB051022: Swift XRT measurement of jet break
  57. GRB051021B: Swift/UVOT Upper limits
  58. GRB 051022: XRT Refined Spectral and Temporal Analysis
  59. GRB051012: Swift-XRT analysis
  60. GRB051021B: Swift XRT refined analysis
  61. GRB 051022: WSRT Radio Detection
  62. GRB 051022: Swift/UVOT Upper Limits
  63. GRB051021A: Swift XRT refined analysis
  64. GRB051022: Optical Observations
  65. GRB 051022, J & K-band observation
  66. GRB051022: Swift XRT Position
  67. GRB051021: Swift/UVOT Upper Limits
  68. GRB 051021B: Refined analysis of the Swift-BAT burst
  69. GRB051021B: Swift XRT Position
  70. GRB 051021B: Swift detection of a burst
  71. GRB051021: Swift XRT analysis
  72. GRB051021.63
  73. Swift-BAT trigger 160640 is not a real GRB
  74. Swift-BAT trigger 160619 is not a GRB
  75. Swift-BAT triggered on a posible CR Shower or possible GRB
  76. GRB 051016A: Swift/UVOT upper limits
  77. GRB 051016B: refined analysis of the Swift/XRT data
  78. GRB 051016B: Swift/UVOT detection
  79. GRB 051016B : Optical follow-up at Lulin
  80. GRB 051016B: Refined analysis of the Swift-BAT burst
  81. GRB 051016B: Swift detection of a soft burst
  82. GRB 051016: Swift-BAT refined analysis
  83. GRB051016 XMM-Newton observation
  84. GRB051016: Swift XRT refined analysis.
  85. GRB051016: Swift detection of a burst
  86. Photometric calibration of Swift/UVOT and Re-analysis of Swift/UVOT GRB 050922C data
  87. GRB 051012: Swift-BAT detection of burst yesterday
  88. Swift trigger 159578 is not a burst
  89. Swift-BAT Trigger 159578 is a possible burst
  90. GRB050805A: Rc optical observations
  91. GRB 051006: Swift/UVOT Upper Limits
  92. GRB 051008 - a low redshift low-luminosity burst?
  93. GRB051008: Swift XRT refined analysis
  94. GRB051008 - Swift UVOT upper limits
  95. Konus-Wind observation of GRB 051008
  96. GRB051008: Final refined analysis of the Swift-BAT burst
  97. GRB 051008: R-band upper limit
  98. GRB051008: Refined analysis of the Swift-BAT burst
  99. GRB 051008: Swift XRT position
  100. GRB 051008: early Swift XRT analysis

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