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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"

26268 results found.

  1. GRB 120913B: Swift detection of a burst
  2. GRB 120913A: Swift detection of a burst
  3. GRB 120907A: optical observations of ISON-Kislovodsk
  4. GRB 120911A: optical upper limit ISON-NM
  5. GRB 120911B: Fermi-LAT detection of a burst
  6. GRB 120911A: Fermi GBM observation
  7. GRB 120911A: Fermi/LAT upper limit
  8. GRB 120911A: Swift/UVOT Upper Limits
  9. GRB 120911A: Swift-XRT refined Analysis
  10. GRB 120911A: Swift-BAT refined analysis
  11. GRB 120911A: Faulkes Telescope North observations
  12. GRB 120911A: Swift-XRT observations
  13. GRB 120911A: ROTSE-III Optical Limits
  14. GRB 120911A: Swift detection of a burst
  15. GRB 120908A and GRB 120909A : Fermi/LAT upper limit
  16. GRB 120908A: Fermi GBM detection
  17. GRB 120908A: Swift Observations
  18. GRB 120909A: TAROT La Silla observatory optical observations
  19. GRB 120909A: Fermi GBM observation
  20. Konus-Wind observation of GRB 120909A
  21. GRB 120909A: Swift/UVOT Detection
  22. GRB 120909A: Swift-XRT refined Analysis
  23. GRB 120909A: Swift-BAT refined analysis
  24. GRB 120909A: GROND detection of the afterglow
  25. Skynet/PROMPT Observations of GRB120909A
  26. GRB 120909A: Swift detection of a burst
  27. GRB 120907A: Swift/UVOT Detection
  28. GRB 120907A: Swift-XRT refined Analysis
  29. GRB 120907A: Fermi GBM detection
  30. GRB 120907A: Swift-BAT refined analysis
  31. GRB 120907A: NOT optical observations
  32. GRB 120907A: ROTSE-III Optical Limits
  33. GRB 120907A: Swift detection of a burst with optical counterpart
  34. GRB 120830A: Further Swift Observations
  35. GRB 120830A: Swift-XRT and UVOT observations
  36. GRB 120830A: Fermi GBM observation
  37. IPN Triangulation of short GRB 120830A
  38. GRB 120830A: Fermi-LAT detection of a short burst
  39. Fermi trigger 368003226 : MASTER optical observations
  40. GRB 120819A: Swift/UVOT Upper Limits
  41. GRB 120817A: Swift/UVOT Upper Limits
  42. GRB 120821A: Swift/XRT observations
  43. GRB 120821A: Swift/UVOT Upper Limits
  44. GRB 120821A: GROND upper limits
  45. GRB 120817A: RAPTOR Limits During Gamma-Ray Emitting Interval
  46. GRB 120817B: BAT location in ground analysis and refined analysis
  47. GRB 120819A: Bassano Bresciano Observatory optical observations
  48. GRB 120819A: Swift-BAT refined analysis
  49. GRB 120819A: GROND afterglow confirmation
  50. GRB 120819A: Swift-XRT refined Analysis
  51. GRB 120819A: Swift detection of a burst
  52. GRB 120817B: Swift-XRT observations
  53. GRB 120816A: Swift/UVOT Detection of the Optical Afterglow
  54. GRB 120817A: Swift-XRT refined Analysis
  55. GRB 120817B: Fermi GBM detection
  56. IPN Triangulation of GRB 120817B (short/very intense)
  57. GRB 120817A: Swift-BAT refined analysis
  58. GRB 120815A: Swift/UVOT Detection of the Optical Afterglow
  59. GRB 120816A: Bassano Bresciano Observatory optical observations
  60. GRB 120817A: FTN and FTS observations
  61. GRB 120816A: Swift-XRT refined Analysis
  62. GRB 120817A: Swift-XRT observations
  63. GRB 120817A: Swift detection of a burst
  64. GRB 120816A: Swift-BAT refined analysis
  65. GRB 120816A: TAROT Calern observatory optical observations
  66. GRB 120816A: ROTSE-III Optical Limits
  67. GRB 120816A: Swift detection of a burst
  68. GRB 120815A: Swift-XRT refined Analysis
  69. GRB 120815A: Swift-BAT refined analysis
  70. GRB 120805A: Liverpool Telescope optical candidate detection
  71. GRB 120815A: GROND afterglow candidate
  72. GRB 120815A: Swift-XRT observations
  73. GRB 120815A: TAROT La Silla observatory optical observations
  74. GRB 120815A: Swift detection of a burst
  75. GRB 120811B: Fermi GBM observation
  76. GCN for GRB 120811C
  77. GRB 120811A: Swift/XRT-UVOT Obseravations
  78. GRB120804A: Chandra observations and afterglow detection
  79. GRB 120811C: Swift-BAT refined analysis
  80. GRB 120811A: Swift-BAT refined analysis
  81. GRB 120811C: NOT redshift
  82. GRB 120811C: Bassano Bresciano Observatory optical observations
  83. GRB 120811C: Swift-XRT refined Analysis
  84. GRB 120811C: Swift/UVOT Detection
  85. GRB 120811C: TAROT Calern observatory optical observations
  86. GRB 120811C: Swift detection of a burst with an optical counterpart
  87. IPN Triangulation of short hard GRB 120811B
  88. Trigger 530588: Swift detection of XMM J174457-2850.3
  89. Swift Trigger 530581: GRB 120811A or a galactic transient
  90. GRB 120807A: Swift/UVOT Upper Limits
  91. GRB 120803A: Confirmation of the X-ray afterglow
  92. GRB 120804A: Konus-Wind and Swift/BAT joint spectral analysis
  93. GRB 120714B: GROND/FORS2 detection of a supernova
  94. Swift Trigger 530441 is a false trigger
  95. GRB 120807A: Swift-XRT refined Analysis
  96. GRB 120807A: Fermi/LAT upper limit
  97. GRB 120807A: RAPTOR Limits During Gamma-Ray Emitting Interval
  98. GRB 120804A: Gemini-North detection of an optical afterglow and putative host galaxy
  99. GRB 120807A: TAROT La Silla observatory optical observations
  100. GRB 120807A: Swift-BAT refined analysis

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