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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"

18438 results found.

  1. GRB 090417B: Swift-XRT refined analysis
  2. GRB 090418: Enhanced Swift-XRT position
  3. GRB 090417B: Swift-BAT further refined analysis
  4. GRB 090418: PAIRITEL NIR detection
  5. GRB 090418: ROTSE-III Confirmation of Optical Counterpart
  6. GRB 090418: Swift detection of a burst with optical afterglow
  7. GRB 090417B: Liverpool Telescope observations
  8. GRB 090417B: Swift-BAT refined analysis
  9. GRB 090417A: Swift-BAT refined analysis
  10. GRB 090417B: Swift detection of a burst
  11. GRB 090417: 2MASS galaxy within BAT Localization
  12. GRB 090417: Swift detection of a short burst
  13. GRB 090410: Suzaku WAM observation of the prompt emission
  14. GRB 090410: Swift-BAT refined analysis
  15. GRB 090410: Swift detection of a burst
  16. Swift-BAT Trigger 348781 is not a GRB
  17. Swift-BAT Trigger 348720 is not a GRB
  18. GRB090408, RIMOTS optical upper limits
  19. Swift-BAT trigger 348781: almost certainly not a burst
  20. GRB 090408B: MASTER II-Kourovka optical observations
  21. GRB 090408: Swift detection of a burst
  22. GRB 090407: Swift-XRT refined analysis
  23. GRB 090407: Swift UVOT Upper Limits
  24. GRB 090407: Enhanced Swift-XRT position
  25. GRB 090407: Swift-BAT refined analysis
  26. GRB 090407: ROTSE-III Optical Limits
  27. GRB 090407: Swift detection of a burst
  28. GRB 090404: millimeter detection
  29. GRB 090404: nIR observations at Calar Alto
  30. Swift/UVOT observations of GRB090404
  31. GRB 090404: optical observations at BOOTES-3 and 1.5-m OSN
  32. GRB 090404: Swift-XRT Team refined analysis
  33. GRB 090404: Swift-BAT refined analysis
  34. GRB 090404: Enhanced Swift-XRT position
  35. GRB 090404: Swift detection of a burst
  36. GRB 090401A: Suzaku WAM observation of the prompt emission
  37. GRB 090401B: Suzaku WAM observation of the prompt emission
  38. Konus-Wind observation of GRB 090401B
  39. GRB 090401B: VLA radio upper limit
  40. GRB090401B, RIMOTS optical upper limits
  41. Swift/UVOT observations of GRB090401B
  42. Swift/UVOT observations of GRB090401B
  43. GRB 090401B: Swift XRT Refined Analysis
  44. Konus-Wind observation of GRB 090401A
  45. GRB 090401B: Enhanced Swift-XRT position
  46. GRB 090401B: Swift-BAT refined analysis
  47. Swift/UVOT detection of GRB090401B
  48. GRB 090401B: Swift detection of a burst
  49. GRB 090401, Swift-BAT refined analysis
  50. GRB 090401: Swift detection of a burst
  51. GRB 090328: Swift XRT refined analysis
  52. GRB 090328: Swift UVOT observations
  53. GRB 090328: Updated position/optical afterglow candidate
  54. GRB 090328: Possible Swift/XRT detection
  55. Fermi LAT and GBM detections of GRB090328
  56. GRB 090323: UVOT Detection of Afterglow
  57. GRB 090323: Swift-XRT refined analysis
  58. GRB 090323: GROND Detection of the Afterglow and Photo-z
  59. GRB 090323: Possible XRT Counterpart
  60. IPN Triangulation of GRB090315 and Tupi Detection of Muon Increase
  61. Further Swift/UVOT observations of GRB 090313
  62. GRB 090313: detection with CARMA in 3mm band
  63. GRB 090313: TAROT La Silla observatory optical detection
  64. GRB 090313: Zadko Telescope observations
  65. GRB 090313 - PAIRITEL NIR detections
  66. GRB 090313: Swift-XRT refined analysis
  67. GRB 090313: Swift/UVOT upper limits
  68. GRB 090313: Faulkes Telescope North observations
  69. GRB 090306B: Confirmation of the X-ray afterglow
  70. GRB 090313: Swift-BAT refined analysis
  71. GRB 090313, GROND observations
  72. GRB 090309, Swift-BAT lag analysis
  73. GRB 090313: Swift detection of a burst
  74. GRB 090313: Swift detection of a burst
  75. Swift trigger 346250 is probably not a burst
  76. GRB 090309A: GROND upper limits
  77. GRB 090307A: TAROT Calern observatory optical observations
  78. GRB 090309: Swift/UVOT Upper Limits
  79. GRB 090309: Swift-XRT refined analysis
  80. GRB 090309: Enhanced Swift-XRT position
  81. GRB 090306B: INTEGRAL SPI-ACS light curve
  82. GRB 090309, Swift-BAT refined analysis
  83. GRB 090308: GROND observations
  84. GRB 090308: Gemini GMOS Observations
  85. GRB 090309: Swift detection of a burst
  86. GRB 090308: Swift/UVOT Upper Limits
  87. GRB 090307: GROND Upper Limits
  88. GRB 090306B: GROND Upper Limits
  89. GRB 090305C: Suzaku WAM observation of the prompt emission
  90. GRB 090308: Swift-XRT refined analysis
  91. Radio observation of GRB 081007 with ATCA
  92. ATCA observation of SGR J1550-5418
  93. GRB 090308: Swift-BAT refined analysis
  94. GRB 090308: Swift detection of a burst
  95. GRB 090306B: Possible XRT afterglow
  96. GRB 090307: Swift-XRT afterglow confirmation and analysis
  97. GRB 090307: Swift-BAT refined analysis of trigger 345551
  98. GRB 090306B: Burst detection from Swift-BAT slew data
  99. Swift Trigger 345551 is probably not a GRB
  100. Swift-BAT trigger 345396 is not a GRB

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