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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"

24376 results found.

  1. Fermi/GBM detection of GRB 081226A
  2. Fermi/GBM detection of GRB 081225
  3. GRB 090107: Swift-BAT refined analysis
  4. GRB 081231: Fermi GBM Detection
  5. GRB 090102: optical decay
  6. Konus-Wind observation of GRB 090102
  7. GRB 081229: Fermi GBM detection
  8. GRB 090102: GROND observations of the optical afterglow
  9. GRB 090102: Swift-BAT refined analysis
  10. GRB 090102: Swift burst of interest
  11. GRB 081230: GROND confirmation of the afterglow
  12. GRB 081230, Swift-BAT refined analysis
  13. GRB081230: Swift-XRT refined analysis
  14. GRB 081230: ROTSE-III Detection of Optical Counterpart
  15. GRB 081226B: Fermi GBM observation
  16. GRB 081226C: Fermi GBM detection
  17. GRB 081228, Swift-BAT refined analysis
  18. GRB 081228: Swift/UVOT Upper Limits
  19. GRB 081228: Swift-XRT Team refined analysis
  20. GRB 081224: Suzaku WAM observation of the prompt emission
  21. GRB 081226: Swift-XRT refined analysis
  22. GRB 081226A: Swift-BAT refined analysis
  23. GRB 081226B: a short-hard GRB detected by INTEGRAL
  24. GRB 081226: ROTSE-III Optical Limits
  25. GRB 081226: Swift detection of a possible short-hard burst
  26. GRB 081211B: optical observations
  27. GRB 081224: Swift-XRT observation
  28. GRB 081224: Fermi GBM Detection & LAT Localization
  29. Konus-Wind observation of GRB 081222
  30. GRB 081223: Fermi GBM detection
  31. GRB 081222: Fermi GBM observation
  32. GRB 081204C: Fermi GBM detection
  33. GRB 081222, Swift-BAT refined analysis
  34. GRB 081221, Swift-BAT refined analysis
  35. Konus-Wind observation of very bright GRB 081215A
  36. GRB081221: Fermi GBM observation
  37. IPN triangulation of bright GRB 081215A
  38. GRB 081221: Swift-XRT Refined Analysis
  39. GRB081222, optical observation
  40. Konus-Wind observation of GRB 081221
  41. GRB 081222: Swift detection of a burst with a bright optical afterglow
  42. GRB 081221: NOT observations
  43. GRB 081217: Fermi GBM detection
  44. GRB 081215B: Fermi GBM detection
  45. GRB 081216: Suzaku WAM observation of the prompt emission
  46. GRB 081216 : Fermi GBM observation
  47. GRB 081215A: Fermi GBM detection
  48. IPN localization of short hard GRB 081216
  49. GRB 081211B - possibly a short burst with extended emission
  50. Fermi Trig Num 251059717 = SGR 0044+42: MASTER prompt optical observations
  51. GRB 0811215A: MASTER prompt optical observations
  52. GRB 081215A: Andromeda inside Fermi error box: MASTER observations
  53. GRB 0811215A: Andromeda inside Fermi error box: MASTER observations
  54. GRB 081213: Fermi GBM detection
  55. Possible GRB 081211B - Swift-XRT analysis
  56. GRB 081207: Fermi GBM detection
  57. GRB 081209: Fermi GBM detection
  58. GRB 081007: Detection of a Supernova
  59. GRB 081211B(?): Possible burst detection from Swift-BAT slew data
  60. GRB 081210: Xinglong TNT R band Upper Limits
  61. GRB 081210, SMARTS optical/IR observations
  62. GRB 081211: Swift-BAT refined analysis
  63. GRB 081211: Swift XRT refined analysis
  64. GRB 081210: Swift-XRT refined analysis
  65. GRB081203B: optical observations
  66. GRB 081210: Swift-BAT refined analysis
  67. IPN triangulation of short hard GRB 081209
  68. GRB 081203A: optical observations
  69. GRB 081206C: Fermi GBM detection
  70. GRB 081206B: Fermi GBM detection
  71. GRB 081206: Fermi GBM detection
  72. GRB 081203B: Suzaku WAM observation of the prompt emission
  73. GRB 081203B: Additional Gemini imaging
  74. GRB081203A: Ashra-1 observation of early optical and VHE-neutrino emission
  75. GRB081203B: optical observations
  76. GRB 081204B: Fermi GBM detection
  77. GRB 081204: Swift XRT afterglow confirmation
  78. GRB 081203A: Skynet/GORT Detections
  79. GRB081203A: optical observation
  80. GRB 081204 : a long GRB localized by INTEGRAL
  81. Konus-Wind observation of GRB 081203A
  82. Konus-Wind observation of GRB 081203B
  83. GRB081203A: Swift-XRT refined analysis
  84. GRB 081203B: optical observations
  85. GRB 081203A: optical observations
  86. Swift UVOT observations of GRB 081203A
  87. GRB 081203A: Burst detection from Swift-BAT slew data
  88. GRB 081203A: Swift-BAT refined analysis
  89. GRB 081130B: MASTER prompt optical observations
  90. GRB 081130B: Fermi GBM detection
  91. GRB 081130: Fermi GBM detection
  92. Swift Trigger 335971: Swift/UVOT Observations
  93. GRB 081126: Fermi GBM detection
  94. GRB 081129: Fermi GBM detection
  95. GRB 081130: MASTER VWF prompt optical observations Fermi GRB
  96. GRB 081128A: optical observations
  97. Swift Trigger 335971 is probably not a real source
  98. Trigger 335971: Swift possible detection of a burst
  99. GRB 081122B: Fermi GBM Detection
  100. GRB 081128: Swift-XRT refined analysis

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