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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"

18476 results found.

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

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