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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"

27046 results found.

  1. Fermi LAT and GBM detections of GRB090328
  2. GRB 090323: TLS detection at 5 days, no break
  3. GRB 090327: Fermi GBM detection
  4. GRB 090323: Lick observations
  5. GRB 090323: Optical observation of xinglong TNT
  6. GRB 090323 TLS detection - still bright
  7. GRB 090323: UVOT Detection of Afterglow
  8. Konus-Wind observation of GRB 090323
  9. GRB 090323 Gemini-South Redshift
  10. GRB 090323: GROND Detection of the Afterglow and Photo-z
  11. SGR J1550-5418: two Fermi GBM triggers on March 22
  12. GRB 090320C: Fermi GBM Detection
  13. Fermi GBM and LAT detections of GRB 090323
  14. GRB 090320B: Fermi GBM detection.
  15. GRB 090319: Fermi GBM detection
  16. GRB 090320A: Fermi GBM detection
  17. GRB 090315: Suzaku WAM observation of the prompt emission
  18. GRB090305B: MASTER-net prompt optical short burst observations
  19. GRB 090313: TAROT La Silla observatory optical detection
  20. GRB 090313: Zadko Telescope observations
  21. GRB 090313 - PAIRITEL NIR detections
  22. GRB 090313: Gemini-S redshift
  23. GRB 090313: Swift-XRT refined analysis
  24. GRB 090313: Swift/UVOT upper limits
  25. GRB 090313: Faulkes Telescope North observations
  26. GRB 090313: Swift-BAT refined analysis
  27. GRB 090313: Sustained optical brightness
  28. GRB 090313, GROND observations
  29. GRB 090313: Swift detection of a burst
  30. GRB 090313: Swift detection of a burst
  31. Swift trigger 346250 is probably not a burst
  32. GRB090310: Fermi GBM detection
  33. GRB 090205: Zadko Telescope late-time observations
  34. GRB 090309A: GROND upper limits
  35. GRB 090307A: TAROT Calern observatory optical observations
  36. GRB 090309: Swift/UVOT Upper Limits
  37. GRB090305B: Fermi GBM detection
  38. GRB 090309B: Fermi GBM detection
  39. GRB 090309: Swift-XRT refined analysis
  40. GRB 090309, Swift-BAT refined analysis
  41. GRB 090308: GROND observations
  42. GRB 090309: Swift detection of a burst
  43. GRB 090308B: Fermi GBM detection
  44. GRB 090308: Swift/UVOT Upper Limits
  45. GRB 090307B: Fermi GBM detection
  46. GRB 090306C: Fermi GBM detection
  47. GRB 090307: GROND Upper Limits
  48. GRB 090306B: GROND Upper Limits
  49. GRB 090305C: Suzaku WAM observation of the prompt emission
  50. GRB 090308: Swift-XRT refined analysis
  51. GRB 090308: Swift-BAT refined analysis
  52. GRB 090308: Swift detection of a burst
  53. GRB 090307: Swift-XRT afterglow confirmation and analysis
  54. GRB 090307: Swift-BAT refined analysis of trigger 345551
  55. Swift Trigger 345551 is probably not a GRB
  56. Swift-BAT trigger 345396 is not a GRB
  57. Fermi GBM trigger 090305784 is not a GRB
  58. GRB 090306: Swift detection of a possible burst
  59. GRB 090305: Swift/UVOT Upper Limits
  60. GRB 090305: Swift-XRT refined analysis
  61. GRB 090305, Swift-BAT refined analysis
  62. GRB 090227A: Suzaku WAM observation of the prompt emission
  63. GRB 090305: Swift detection of a short burst
  64. GRB 090303: Fermi GBM detection
  65. GRB 090304: Fermi GBM detection
  66. GRB 090301A: Suzaku WAM observation of the prompt emission
  67. Konus-RF catches first GRB and SGR bursts
  68. GRB 090228B: Fermi GBM detection
  69. Konus-Wind observation of bright short GRB 090227B
  70. IPN localization of short bright GRB 090227B
  71. Konus-Wind observation of GRB 090301A
  72. GRB 090301A: Swift-BAT refined analysis
  73. GRB 090301B: Fermi GBM detection
  74. GRB 090227B: Fermi GBM detection
  75. GRB 090301: Swift detection of a burst
  76. Swift_BAT_Lightcurve Notice for Trigger Number 344565 is not valid
  77. GRB 090228: Fermi GBM detection
  78. GRB 090227: Fermi GBM detection
  79. GRB 090206: Fermi GBM detection
  80. SGR J1550-5418
  81. Ongoing activity of AXP/SGR 1E1547.0-5408
  82. GRB 090222: Fermi GBM detection
  83. GRB 090219: Fermi GBM detection
  84. Swift Trigger 343319 is not a GRB
  85. GRB 090217: Suzaku WAM observation of the prompt emission
  86. GRB090217: XRT analysis
  87. Konus-Wind observation of GRB 090217
  88. IPN localization of GRB 090217
  89. GRB 090213: Fermi GBM detection
  90. GRB090217: Fermi-LAT Detection
  91. GRB 090217: Fermi GBM detection
  92. SGR activity seen by BAT during ICSP Ionospheric Events
  93. GRB 090207 - Fermi GBM Observations
  94. Fermi Gamma-ray Burst Monitor trigger 255729682 is not a GRB
  95. GRB 090129: Fermi GBM detection
  96. Fermi Gamma-ray Burst Monitor trigger 255541748 cannot be classified
  97. GRB 090205: Swift/UVOT Upper Limits
  98. GRB 090205: GROND observations and photometric redshift estimate
  99. GRB 090205: Swift-BAT refined analysis
  100. GRB 090205: Swift detection of a burst

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