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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"

19603 results found.

  1. GRB 090404: Swift-BAT refined analysis
  2. GRB 090404: Enhanced Swift-XRT position
  3. GRB 090404: Swift detection of a burst
  4. GRB 090401A: Suzaku WAM observation of the prompt emission
  5. GRB 090401B: Suzaku WAM observation of the prompt emission
  6. Konus-Wind observation of GRB 090401B
  7. GRB 090401B: VLA radio upper limit
  8. GRB090401B, RIMOTS optical upper limits
  9. Swift/UVOT observations of GRB090401B
  10. Swift/UVOT observations of GRB090401B
  11. GRB 090401B: Swift XRT Refined Analysis
  12. Konus-Wind observation of GRB 090401A
  13. GRB 090401B: Enhanced Swift-XRT position
  14. GRB 090401B: Swift-BAT refined analysis
  15. Swift/UVOT detection of GRB090401B
  16. GRB 090401B: Swift detection of a burst
  17. GRB 090401, Swift-BAT refined analysis
  18. GRB 090401: Swift detection of a burst
  19. GRB 090328: Swift XRT refined analysis
  20. GRB 090328: Swift UVOT observations
  21. GRB 090328: Updated position/optical afterglow candidate
  22. GRB 090328: Possible Swift/XRT detection
  23. Fermi LAT and GBM detections of GRB090328
  24. GRB 090323: UVOT Detection of Afterglow
  25. GRB 090323: Swift-XRT refined analysis
  26. GRB 090323: GROND Detection of the Afterglow and Photo-z
  27. GRB 090323: Possible XRT Counterpart
  28. IPN Triangulation of GRB090315 and Tupi Detection of Muon Increase
  29. Further Swift/UVOT observations of GRB 090313
  30. GRB 090313: detection with CARMA in 3mm band
  31. GRB 090313: TAROT La Silla observatory optical detection
  32. GRB 090313: Zadko Telescope observations
  33. GRB 090313 - PAIRITEL NIR detections
  34. GRB 090313: Swift-XRT refined analysis
  35. GRB 090313: Swift/UVOT upper limits
  36. GRB 090313: Faulkes Telescope North observations
  37. GRB 090306B: Confirmation of the X-ray afterglow
  38. GRB 090313: Swift-BAT refined analysis
  39. GRB 090313, GROND observations
  40. GRB 090309, Swift-BAT lag analysis
  41. GRB 090313: Swift detection of a burst
  42. GRB 090313: Swift detection of a burst
  43. Swift trigger 346250 is probably not a burst
  44. GRB 090309A: GROND upper limits
  45. GRB 090307A: TAROT Calern observatory optical observations
  46. GRB 090309: Swift/UVOT Upper Limits
  47. GRB 090309: Swift-XRT refined analysis
  48. GRB 090309: Enhanced Swift-XRT position
  49. GRB 090306B: INTEGRAL SPI-ACS light curve
  50. GRB 090309, Swift-BAT refined analysis
  51. GRB 090308: GROND observations
  52. GRB 090308: Gemini GMOS Observations
  53. GRB 090309: Swift detection of a burst
  54. GRB 090308: Swift/UVOT Upper Limits
  55. GRB 090307: GROND Upper Limits
  56. GRB 090306B: GROND Upper Limits
  57. GRB 090305C: Suzaku WAM observation of the prompt emission
  58. GRB 090308: Swift-XRT refined analysis
  59. Radio observation of GRB 081007 with ATCA
  60. ATCA observation of SGR J1550-5418
  61. GRB 090308: Swift-BAT refined analysis
  62. GRB 090308: Swift detection of a burst
  63. GRB 090306B: Possible XRT afterglow
  64. GRB 090307: Swift-XRT afterglow confirmation and analysis
  65. GRB 090307: Swift-BAT refined analysis of trigger 345551
  66. GRB 090306B: Burst detection from Swift-BAT slew data
  67. Swift Trigger 345551 is probably not a GRB
  68. Swift-BAT trigger 345396 is not a GRB
  69. IPN localization of short GRB 090305C
  70. GRB 090306: Swift detection of a possible burst
  71. GRB 090305: Swift/UVOT Upper Limits
  72. GRB 090305: Swift-XRT refined analysis
  73. GRB 090305, Swift-BAT refined analysis
  74. GRB 090305: Swift detection of a short burst
  75. GRB 090301A: Suzaku WAM observation of the prompt emission
  76. Konus-Wind observation of GRB 090301A
  77. GRB 090301A: Swift-BAT refined analysis
  78. GRB 090301: Swift detection of a burst
  79. Swift_BAT_Lightcurve Notice for Trigger Number 344565 is not valid
  80. SGR J1550-5418
  81. GRB 081211B: Nearby cluster
  82. Swift Restored
  83. Swift Trigger 343319 is not a GRB
  84. GRB090217: XRT analysis
  85. SGR activity seen by BAT during ICSP Ionospheric Events
  86. GRB 090129: Fermi GBM detection
  87. GRB 090205: Swift/UVOT Upper Limits
  88. GRB 090205: Swift-XRT refined analysis
  89. GRB 090205: Swift burst of interest
  90. GRB 090205: GROND observations and photometric redshift estimate
  91. GRB 090205: Swift-BAT refined analysis
  92. GRB 090205: Enhanced Swift-XRT position
  93. GRB 090205: Swift detection of a burst
  94. GRB 090126A: Swift-XRT afterglow confirmation
  95. Konus-Wind observation of GRB 090201
  96. GRB 090201: Swift-XRT refined analysis
  97. GRB090201: Swift UVOT upper limits
  98. GRB 090201: Enhanced Swift-XRT position
  99. GRB 090201: Swift-BAT refined analysis
  100. GRB 090201: Swift-XRT detection of the possible X-ray afterglow

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