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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"

28051 results found.

  1. GRB 081228, Swift-BAT refined analysis
  2. VLA radio detection of GRB 081221
  3. GRB 081228: Swift/UVOT Upper Limits
  4. GRB 081228: Swift-XRT Team refined analysis
  5. GRB 081228: detection by GROND
  6. GRB 081228: Enhanced Swift-XRT position
  7. GRB 081228: TAROT Calern observatory optical observations
  8. GRB 081228: Swift detection of a burst
  9. VLA radio observation of GRB 081221
  10. GRB 081226B: Swift XRT and UVOT upper limits
  11. GRB 081224: Suzaku WAM observation of the prompt emission
  12. GRB 081226: Swift-XRT refined analysis
  13. GRB 081226A: Swift UVOT Upper Limits
  14. GRB 081226A: Swift-BAT refined analysis
  15. GRB 081226: GROND afterglow candidate
  16. GRB 081226: ROTSE-III Optical Limits
  17. GRB 081226: Swift detection of a possible short-hard burst
  18. GRB 080810: optical observations
  19. GRB 081211B: optical observations
  20. GRB 081224: Swift-XRT observation
  21. GRB 081222: MITSuME optical observation
  22. GRB 081224: Fermi GBM Detection & LAT Localization
  23. GRB 080810: optical observations
  24. Konus-Wind observation of GRB 081222
  25. GRB 081223: Fermi GBM detection
  26. GRB 081221: GROND observations
  27. VLA radio upper limit on GRB 081222
  28. GRB 081222: Fermi GBM observation
  29. GRB 081221: Probable host galaxy in Keck imaging
  30. GRB 081204C: Fermi GBM detection
  31. GRB 081222, Swift-BAT refined analysis
  32. GRB 081221, Swift-BAT refined analysis
  33. GRB081222 optical limit by "Pi of the Sky"
  34. GRB 081222: Swift XRT refined analysis
  35. GRB081221: Fermi GBM observation
  36. IPN triangulation of bright GRB 081215A
  37. GRB 081222: Faulkes Telescope South observations
  38. GRB 081221: Gemini-N nIR imaging
  39. GRB081222, optical observation
  40. GRB081203A: BTA observation
  41. Konus-Wind observation of GRB 081221
  42. GRB 081222: GROND Detection of the Optical/NIR Afterglow
  43. GRB081222: REM candidate afterglow
  44. GRB 081222: Swift detection of a burst with a bright optical afterglow
  45. GRB 081221: Enhanced Swift-XRT position
  46. GRB 081221: further NOT observations
  47. GRB 081221: NOT observations
  48. GRB 081221: Swift detection of a burst
  49. GRB 081217: Fermi GBM detection
  50. GRB 081211B: Further Swift-XRT analysis
  51. GRB 081215B: Fermi GBM detection
  52. GRB 081216: Suzaku WAM observation of the prompt emission
  53. GRB 081216 : Fermi GBM observation
  54. GRB 081215A: Fermi GBM detection
  55. GRB 081118: Zadko observations
  56. Fermi Trig Num 251059717 = SGR 0044+42: MASTER prompt optical observations
  57. GRB 0811215A: MASTER prompt optical observations
  58. GRB 081215A: Andromeda inside Fermi error box: MASTER observations
  59. GRB 0811215A: Andromeda inside Fermi error box: MASTER observations
  60. Possible GRB 081211B: Swift/UVOT Upper Limits
  61. GRB 081213: Fermi GBM detection
  62. Possible GRB 081211B - Swift-XRT analysis
  63. GRB 081207: Fermi GBM detection
  64. GRB 081209: Fermi GBM detection
  65. GRB 081211B(?): Possible burst detection from Swift-BAT slew data
  66. GRB 081210, SMARTS optical/IR observations
  67. GRB 081211: Swift-BAT refined analysis
  68. GRB 081211: Swift XRT refined analysis
  69. GRB 081211: Enhanced Swift-XRT position
  70. GRB 081211: Swift detection of a burst
  71. GRB 081210: Swift-XRT refined analysis
  72. GRB081203B: optical observations
  73. GRB 081210: Enhanced Swift-XRT position
  74. GRB 081210: Swift-BAT refined analysis
  75. GRB 081210: Swift detection of a burst with optical afterglow
  76. IPN triangulation of short hard GRB 081209
  77. GRB 081203A: optical observations
  78. GRB 081206C: Fermi GBM detection
  79. Radio observation of GRB 081121 with ATCA
  80. Radio observation of GRB 081118 with ATCA
  81. GRB 081206B: Fermi GBM detection
  82. GRB 081206: Fermi GBM detection
  83. GRB 081128: afterglow observations
  84. GRB 081203B: Suzaku WAM observation of the prompt emission
  85. Radio observation of GRB 081109 with ATCA
  86. Radio observation of GRB 081104 with ATCA
  87. Radio observation of GRB 081029 with ATCA
  88. Radio observation of GRB 081008 with ATCA
  89. GRB081203A: Ashra-1 observation of early optical and VHE-neutrino emission
  90. GRB081203A: Optical observations at Ishigaki
  91. GRB 081204: GROND Observations
  92. Radio detection of GRB 081203B with the VLA
  93. GRB081203A: Radio upper limit at 15 GHz
  94. GRB 081204B: Fermi GBM detection
  95. GRB 081204: Swift/UVOT Upper Limits
  96. GRB 081204: Swift XRT afterglow confirmation
  97. GRB081203A: MITSuME optical observation
  98. GRB081203A: optical observation
  99. GRB 081204 : a long GRB localized by INTEGRAL
  100. VLA Radio upper limit on GRB 081203A

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