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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"

18732 results found.

  1. GRB 051117B: ROTSE-III Optical Limits
  2. GRB051117B: Swift XRT position
  3. GRB 051117B: Swift detection of a burst
  4. GRB 051117: Swift detection of a bright burst
  5. GRB051114: results of the Swift-XRT observation
  6. GRB 051114: Swift-BAT refined analysis
  7. GRB050925: analysis of the XMM-Newton observation
  8. GRB 051114: Swift-BAT detection of a short burst
  9. GRB 051113: Swift-BAT refined analysis
  10. GRB 051113: Swift-BAT detection of a burst
  11. GRB 051111: AEOS optical observations
  12. GRB 051109A Milagro GeV/TeV Observations
  13. GRB/SGR 050925: XMM-Newton ToO observation
  14. GRB051111: Swift/UVOT Observations
  15. GRB051111: XRT preliminary analysis
  16. GRB 051111: Swift-BAT refined analysis
  17. GRB 051109A Optical Observations
  18. GRB051111a: SARA Observations
  19. GRB 051111A: KAIT optical observations
  20. GRB051111: Super-LOTIS Early Detection
  21. GRB 051111: ROTSE-III Analysis of Prompt Counterpart
  22. Faulkes Telescope R-band detection of GRB051111
  23. GRB051111: Swift-BAT detection of a bright burst
  24. GRB 051111A: ROTSE-III Detection of Possible Counterpart
  25. Early RAPTOR measurements of GRB 051109a - the movie.
  26. Konus-Wind observation of GRB 051109A
  27. GRB 051109B: Swift-BAT refined analysis
  28. GRB 051109B: ROTSE-III Optical Limits
  29. GRB 051109A: Swift-UVOT Observations
  30. IPN triangulation and Konus spectrum of the short/soft GRB051107 (large
  31. GRB051109B: no UVOT source detected
  32. GRB051109B: XRT refined analysis
  33. GRB 051109B : Lulin Optical Observations
  34. GRB051109A: further steepening in the X-ray light curve
  35. GRB051109A: XRT refined analysis
  36. GRB051109B: XRT position
  37. GRB 051109B: Super-LOTIS Observations
  38. GRB 051109B Kiso optical follow-up observation
  39. GRB 051109B: Swift detection of a burst
  40. GRB051109: Early Super-LOTIS Detection
  41. GRB 051109: Swift-BAT refined analysis
  42. GRB 051109a: MDM Observations
  43. GRB 051109A: ROTSE-III Decline rate for Optical Counterpart
  44. GRB051109: Swift detection of a burst
  45. GRB 051109a: IR Detections
  46. GRB 051109: ROTSE-III Detection of Possible Counterpart
  47. GRB051105B: Swift/XRT upper limit
  48. GRB051105B: Swift/UVOT upper limit
  49. GRB051103: MASTER: OT limit and host galaxy candidates
  50. GRB051028: Swift-XRT refined analysis
  51. GRB 051105a: MDM Observations
  52. GRB051105A: Swift/UVOT Observations
  53. IPN triangulation and Konus spectrum of the bright short/hard GRB051103
  54. XRT observations of GRB 051105A
  55. GRB 051105: Swift-BAT improved refined analysis
  56. GRB 051105: Swift-BAT refined analysis
  57. GRB 051105: Swift detection of a short burst
  58. GRB051028: Swift/UVOT upper limits
  59. GRB051028: Swift XRT Position
  60. GRB 051022: XRT Refined Spectral and Temporal Analysis--Correction
  61. GRB051022: Swift XRT measurement of jet break
  62. SGR 1806-20: continued moderate activity seen with INTEGRAL
  63. GRB051021B: Swift/UVOT Upper limits
  64. GRB 051022: XRT Refined Spectral and Temporal Analysis
  65. GRB051012: Swift-XRT analysis
  66. GRB051021B: Swift XRT refined analysis
  67. GRB 051022: WSRT Radio Detection
  68. GRB 051022: Swift/UVOT Upper Limits
  69. GRB051021A: Swift XRT refined analysis
  70. GRB051022: Optical Observations
  71. GRB 051022, J & K-band observation
  72. GRB051022: Swift XRT Position
  73. GRB051021: Swift/UVOT Upper Limits
  74. GRB 051021B: Refined analysis of the Swift-BAT burst
  75. GRB051021B: Swift XRT Position
  76. GRB 051021B: Swift detection of a burst
  77. GRB051021: Swift XRT analysis
  78. GRB051021.63
  79. Swift-BAT trigger 160640 is not a real GRB
  80. Swift-BAT trigger 160619 is not a GRB
  81. Swift-BAT triggered on a posible CR Shower or possible GRB
  82. GRB 051016A: Swift/UVOT upper limits
  83. GRB 051016B: refined analysis of the Swift/XRT data
  84. GRB 051016B: Swift/UVOT detection
  85. GRB 051016B : Optical follow-up at Lulin
  86. GRB 051016B: Refined analysis of the Swift-BAT burst
  87. GRB 051016B: Swift detection of a soft burst
  88. GRB 051016: Swift-BAT refined analysis
  89. GRB051016 XMM-Newton observation
  90. GRB051016: Swift XRT refined analysis.
  91. GRB051016: Swift detection of a burst
  92. Photometric calibration of Swift/UVOT and Re-analysis of Swift/UVOT GRB 050922C data
  93. GRB 051012: Swift-BAT detection of burst yesterday
  94. Swift trigger 159578 is not a burst
  95. Swift-BAT Trigger 159578 is a possible burst
  96. GRB050805A: Rc optical observations
  97. GRB 051006: Swift/UVOT Upper Limits
  98. GRB 051008 - a low redshift low-luminosity burst?
  99. GRB051008: Swift XRT refined analysis
  100. GRB051008 - Swift UVOT upper limits

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