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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

27938 results found.

  1. Swift-BAT trigger 349718 is not a burst
  2. GRB 090417B: Optical observation
  3. GRB 090418A: optical observations
  4. GRB 090419: Swift/UVOT Observations
  5. GRB 090418B: Faulkes Telescope North observations
  6. GRB 090418A: Swift/UVOT Observations
  7. GRB 090417B: Swift/UVOT Upper Limits
  8. GRB 090417B Correction to the BAT refined analysis position
  9. GRB 090419: Swift-XRT refined analysis
  10. Konus-Wind observation of GRB 090418B
  11. GRB 090419: GROND detection of afterglow candidate
  12. GRB 090419: Swift-BAT refined analysis
  13. VLA radio detection of GRB 090418
  14. VLA radio upper limit on GRB 090417B
  15. GRB 090419: Enhanced Swift-XRT position
  16. GRB 090418: Swift XRT refined analysis
  17. GRB 090418A: ROTSE-III Refined Analysis
  18. GRB 090419: Swift detection of a burst
  19. GRB 090418B: Detection of a bright burst from Swift-BAT slew data
  20. GRB 090418: Swift-BAT refined analysis
  21. GRB 090417B: Swift-XRT refined analysis
  22. GRB 090418: Enhanced Swift-XRT position
  23. GRB 090417B: Swift-BAT further refined analysis
  24. GRB 090418: PAIRITEL NIR detection
  25. GRB 090418: ROTSE-III Confirmation of Optical Counterpart
  26. GRB 090418: Swift detection of a burst with optical afterglow
  27. GRB 090417B: Liverpool Telescope observations
  28. GRB 090417B: Swift-BAT refined analysis
  29. GRB 090417A: Swift-BAT refined analysis
  30. GRB 090417B: Swift detection of a burst
  31. GRB 090417: 2MASS galaxy within BAT Localization
  32. GRB 090417: Swift detection of a short burst
  33. GRB 090412: Fermi GBM detection
  34. GRB 090411B: Fermi GBM detection
  35. GRB 090411A: Fermi GBM detection
  36. GRB 090410: Suzaku WAM observation of the prompt emission
  37. GRB 090410: Swift-BAT refined analysis
  38. GRB 090410: Swift detection of a burst
  39. GRB 090409: Fermi GBM detection
  40. Swift-BAT Trigger 348781 is not a GRB
  41. Swift-BAT Trigger 348720 is not a GRB
  42. GRB090408, RIMOTS optical upper limits
  43. Swift-BAT trigger 348781: almost certainly not a burst
  44. Fermi GBM Detection of a weak source
  45. GRB 090408B: MASTER II-Kourovka optical observations
  46. GRB 090408: Swift detection of a burst
  47. GRB 090407: Swift-XRT refined analysis
  48. GRB 090407: Swift UVOT Upper Limits
  49. GRB 090407: Enhanced Swift-XRT position
  50. GRB 090407: Swift-BAT refined analysis
  51. GRB 090407: ROTSE-III Optical Limits
  52. GRB 090407: Swift detection of a burst
  53. GRB 090404: millimeter detection
  54. GRB 090404: nIR observations at Calar Alto
  55. GRB 090405: Fermi GBM Detection
  56. GRB 090403: Fermi GBM detection
  57. Swift/UVOT observations of GRB090404
  58. GRB 090404: optical observations at BOOTES-3 and 1.5-m OSN
  59. GRB 090404: Swift-XRT Team refined analysis
  60. GRB 090404: Swift-BAT refined analysis
  61. GRB 090404: Enhanced Swift-XRT position
  62. GRB 090404: Swift detection of a burst
  63. GRB 090401A: Suzaku WAM observation of the prompt emission
  64. GRB 090401B: Suzaku WAM observation of the prompt emission
  65. Konus-Wind observation of GRB 090401B
  66. GRB 090401B: VLA radio upper limit
  67. GRB090401B, RIMOTS optical upper limits
  68. Swift/UVOT observations of GRB090401B
  69. GRB 090401B: AGILE refined analysis
  70. Swift/UVOT observations of GRB090401B
  71. GRB 090401B: Swift XRT Refined Analysis
  72. GRB 090331: Fermi GBM detection
  73. Konus-Wind observation of GRB 090401A
  74. GRB 090401B: Enhanced Swift-XRT position
  75. AGILE Gamma-ray detection of GRB 090401B
  76. GRB 090401B: Swift-BAT refined analysis
  77. Swift/UVOT detection of GRB090401B
  78. GRB 090401B: Swift detection of a burst
  79. GRB 090401, Swift-BAT refined analysis
  80. GRB 090323: Further TLS detections - a break?
  81. GRB 090401: Swift detection of a burst
  82. GRB 090328: Radio afterglow detection
  83. GRB 090326: Fermi GBM detection
  84. GRB 090328: BOOTES-3 optical observations
  85. GRB 090328B: Fermi GBM Detection
  86. GRB 090330: Fermi GBM detection
  87. GRB 090328: GROND Detection of the Optical/NIR Afterglow
  88. GRB 090328: Swift XRT refined analysis
  89. GRB 090328: Swift UVOT observations
  90. GRB 090323: WSRT Radio Detection
  91. GRB 090328: Updated position/optical afterglow candidate
  92. GRB 090328: Possible Swift/XRT detection
  93. Fermi LAT and GBM detections of GRB090328
  94. GRB 090323: Radio afterglow detection
  95. GRB 090323: TLS detection at 5 days, no break
  96. GRB 090327: Fermi GBM detection
  97. GRB 090323 TLS detection - still bright
  98. GRB 090323: UVOT Detection of Afterglow
  99. GRB 090323: Swift-XRT refined analysis
  100. GRB 090323: GROND Detection of the Afterglow and Photo-z

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