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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"

18544 results found.

  1. GRB051028: Swift XRT Position
  2. GRB 051022: XRT Refined Spectral and Temporal Analysis--Correction
  3. GRB051022: Swift XRT measurement of jet break
  4. GRB051021B: Swift/UVOT Upper limits
  5. GRB 051022: XRT Refined Spectral and Temporal Analysis
  6. GRB051012: Swift-XRT analysis
  7. GRB051021B: Swift XRT refined analysis
  8. GRB 051022: WSRT Radio Detection
  9. GRB 051022: Swift/UVOT Upper Limits
  10. GRB051021A: Swift XRT refined analysis
  11. GRB051022: Optical Observations
  12. GRB 051022, J & K-band observation
  13. GRB051022: Swift XRT Position
  14. GRB051021: Swift/UVOT Upper Limits
  15. GRB 051021B: Refined analysis of the Swift-BAT burst
  16. GRB051021B: Swift XRT Position
  17. GRB 051021B: Swift detection of a burst
  18. GRB051021: Swift XRT analysis
  19. GRB051021.63
  20. Swift-BAT trigger 160640 is not a real GRB
  21. Swift-BAT trigger 160619 is not a GRB
  22. Swift-BAT triggered on a posible CR Shower or possible GRB
  23. GRB 051016A: Swift/UVOT upper limits
  24. GRB 051016B: refined analysis of the Swift/XRT data
  25. GRB 051016B: Swift/UVOT detection
  26. GRB 051016B : Optical follow-up at Lulin
  27. GRB 051016B: Refined analysis of the Swift-BAT burst
  28. GRB 051016B: Swift detection of a soft burst
  29. GRB 051016: Swift-BAT refined analysis
  30. GRB051016 XMM-Newton observation
  31. GRB051016: Swift XRT refined analysis.
  32. GRB051016: Swift detection of a burst
  33. Photometric calibration of Swift/UVOT and Re-analysis of Swift/UVOT GRB 050922C data
  34. GRB 051012: Swift-BAT detection of burst yesterday
  35. Swift trigger 159578 is not a burst
  36. Swift-BAT Trigger 159578 is a possible burst
  37. GRB050805A: Rc optical observations
  38. GRB 051006: Swift/UVOT Upper Limits
  39. GRB 051008 - a low redshift low-luminosity burst?
  40. GRB051008: Swift XRT refined analysis
  41. GRB051008 - Swift UVOT upper limits
  42. Konus-Wind observation of GRB 051008
  43. GRB051008: Final refined analysis of the Swift-BAT burst
  44. GRB 051008: R-band upper limit
  45. GRB051008: Refined analysis of the Swift-BAT burst
  46. GRB 051008: Swift XRT position
  47. GRB 051008: early Swift XRT analysis
  48. GRB 051008: Swift UVOT Candidate
  49. GRB051008: Swift-BAT detection of a bright burst
  50. GRB 051006: XRT refined analysis
  51. Swift-BAT trigger 158700 is a probable Cosmic Ray Shower Event
  52. GRB 051006: optical observations at Sierra Nevada
  53. GRB051006: Refined analysis of the Swift-BAT burst
  54. GRB 051006: XRT position
  55. GRB051006: Swift detection of a burst
  56. Swift-BAT triggers 158261 and 158262 Retraction
  57. GRB051001: Swift UVOT Upper Limits
  58. GRB 050925: Second Epoch WSRT Radio Observations
  59. GRB 051001: Swift XRT refined analysis
  60. GRB 051001, optical observations at Mt. John
  61. GRB 051001: I-band limit
  62. GRB 051001: Swift-BAT refined analysis
  63. GRB 051001: Swift Detection of a Burst
  64. GRB 051001: ROTSE-III Optical Limits
  65. GRB050922B: optical limit
  66. GRB050925: Swift/XRT limits
  67. GRB/SGR 050925: IR Observations
  68. GRB050922C - Swift UVOT preliminary analysis
  69. GRB 050925: WSRT Radio Observations
  70. GRB050925: Swift UVOT upper limits
  71. Refined analysis of the Swift-BAT soft short burst
  72. GRB050925: Faulkes Telescope North R-band limit
  73. GRB050925: Swift-BAT detection of a short burst
  74. GRB 050922B: Correction to BAT refined analysis, longer burst
  75. GRB050922B: refined XRT analysis
  76. Konus-Wind observation of GRB 050922C
  77. GRB050922B: Swift UVOT early upper limits.
  78. GRB 050922B: optical limit
  79. GRB 050922C: Swift XRT refined analysis
  80. HETE Fregate observations of GRB 050922C
  81. GRB 050922C: Swift-BAT refined analysis
  82. GRB 050922B: Swift-BAT refined analysis
  83. GRB050922C: optical observations
  84. GRB 050922C: Absorption redshift from the Nordic Optical Telescope
  85. GRB 050922C: optical obserations
  86. GRB 050922C: NOT optical observations
  87. GRB 050922A: Analysis of Swift/XRT TOO observation
  88. GRB 050922C: Swift detection of a bright burst
  89. GRB 050922C: ROTSE-IIId Refined Analysis
  90. GRB 050922C: ROTSE-III Detection of Possible Counterpart
  91. GRB 050922B: ROTSE-III Optical Limits
  92. GRB 050922B,optical observation
  93. GRB050922B: Swift-BAT detection of a weak long burst
  94. GRB050918: Possible Swift/XRT detected afterglow
  95. GRB050820B: analysis of the XMM-Newton observation
  96. GRB050916: Swift/UVOT Upper Limits
  97. GRB 050916: Swift-BAT refined analysis
  98. Swift-BAT trigger 155764 is not a GRB
  99. Swift-BAT trigger 155764 is probably not a GRB
  100. Swift trigger 155764: bad XRT centroid

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