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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"

24190 results found.

  1. Fermi GBM trigger 261106787 is not a GRB
  2. GRB 090410: MITSuME optical upper limits
  3. GRB 090410: Swift-BAT refined analysis
  4. GRB 090410: Swift detection of a burst
  5. GRB090408 : TAOS optical observations
  6. GRB 090409: Fermi GBM detection
  7. Swift-BAT Trigger 348781 is not a GRB
  8. Swift-BAT Trigger 348720 is not a GRB
  9. GRB090408, RIMOTS optical upper limits
  10. GRB 090408: Xinglong TNT optical Upper Limit
  11. Swift-BAT trigger 348781: almost certainly not a burst
  12. Fermi GBM Detection of a weak source
  13. GRB 090408B: MASTER II-Kourovka optical observations
  14. GRB 090408: Swift detection of a burst
  15. GRB 090407: Swift-XRT refined analysis
  16. GRB 090407: Swift UVOT Upper Limits
  17. GRB 090407: Swift-BAT refined analysis
  18. GRB 090407: ROTSE-III Optical Limits
  19. GRB 090407: Swift detection of a burst
  20. GRB 090405: Fermi GBM Detection
  21. GRB 090403: Fermi GBM detection
  22. Swift/UVOT observations of GRB090404
  23. GRB 090404: optical observations at BOOTES-3 and 1.5-m OSN
  24. GRB 090404: Swift-XRT Team refined analysis
  25. GRB 090404: Xinglong TNT optical Upper Limit
  26. GRB 090404: Swift-BAT refined analysis
  27. Fermi Gamma-ray Burst Monitor trigger 260428446 is not a GRB
  28. GRB 090404: Swift detection of a burst
  29. GRB 090401A: Suzaku WAM observation of the prompt emission
  30. GRB 090401B: Suzaku WAM observation of the prompt emission
  31. Konus-Wind observation of GRB 090401B
  32. GRB 090401B: Xinglong TNT optical Upper Limit
  33. GRB090401B, RIMOTS optical upper limits
  34. GRB 090328: Fermi-LAT refined analysis
  35. Swift/UVOT observations of GRB090401B
  36. GRB 090401B: AGILE refined analysis
  37. Swift/UVOT observations of GRB090401B
  38. GRB 090401B: Swift XRT Refined Analysis
  39. GRB 090331: Fermi GBM detection
  40. Konus-Wind observation of GRB 090401A
  41. GRB 090401B: Swift-BAT refined analysis
  42. GRB 090401B: Swift detection of a burst
  43. GRB 090401, Swift-BAT refined analysis
  44. GRB 090323: Further TLS detections - a break?
  45. GRB 090401: Swift detection of a burst
  46. GRB 090326: Fermi GBM detection
  47. GRB 090328B: Fermi GBM Detection
  48. GRB 090330: Fermi GBM detection
  49. GRB 090328: GROND Detection of the Optical/NIR Afterglow
  50. GRB 090328: Swift XRT refined analysis
  51. Konus-Wind observation of GRB 090328
  52. GRB 090328: Swift UVOT observations
  53. Fermi LAT and GBM detections of GRB090328
  54. GRB 090323: TLS detection at 5 days, no break
  55. GRB 090327: Fermi GBM detection
  56. GRB 090320B: MASTER-Net prompt optical observations
  57. GRB 090323: Lick observations
  58. GRB 090323: Optical observation of xinglong TNT
  59. GRB 090323 TLS detection - still bright
  60. GRB 090323: UVOT Detection of Afterglow
  61. Konus-Wind observation of GRB 090323
  62. GRB 090323 Gemini-South Redshift
  63. GRB 090323: GROND Detection of the Afterglow and Photo-z
  64. SGR J1550-5418: two Fermi GBM triggers on March 22
  65. GRB 090320C: Fermi GBM Detection
  66. Fermi GBM and LAT detections of GRB 090323
  67. GRB 090320B: Fermi GBM detection.
  68. GRB 090319: Fermi GBM detection
  69. GRB 090320A: Fermi GBM detection
  70. IPN Triangulation of GRB090315 and Tupi Detection of Muon Increase
  71. GRB090305B: MASTER-net prompt optical short burst observations
  72. GRB 090313: TAROT La Silla observatory optical detection
  73. GRB 090313: Zadko Telescope observations
  74. GRB 090313 - PAIRITEL NIR detections
  75. GRB 090313: Gemini-S redshift
  76. GRB 090313: Swift-XRT refined analysis
  77. GRB 090313: Swift/UVOT upper limits
  78. GRB 090313: Faulkes Telescope North observations
  79. GRB 090306B: Confirmation of the X-ray afterglow
  80. GRB 090313: Swift-BAT refined analysis
  81. GRB 090313: Sustained optical brightness
  82. GRB 090313, GROND observations
  83. GRB 090309, Swift-BAT lag analysis
  84. GRB 090313: Swift detection of a burst
  85. GRB 090313: Swift detection of a burst
  86. Swift trigger 346250 is probably not a burst
  87. GRB090310: Fermi GBM detection
  88. GRB 090205: Zadko Telescope late-time observations
  89. GRB 090309A: GROND upper limits
  90. GRB 090307A: TAROT Calern observatory optical observations
  91. GRB 090309: Swift/UVOT Upper Limits
  92. GRB090305B: Fermi GBM detection
  93. GRB 090309B: Fermi GBM detection
  94. GRB 090309: Swift-XRT refined analysis
  95. GRB 090306B: INTEGRAL SPI-ACS light curve
  96. GRB 090309, Swift-BAT refined analysis
  97. GRB 090308: GROND observations
  98. GRB 090309: Swift detection of a burst
  99. GRB 090308B: Fermi GBM detection
  100. GRB 090308: Swift/UVOT Upper Limits

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