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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"

11515 results found.

  1. GRB 090616: Fermi GBM detection
  2. GRB 090612: Fermi GBM detection
  3. GRB 090610C: Fermi GBM detection
  4. GRB 090610B: Fermi GBM detection
  5. GRB 090610: Fermi GBM detection
  6. SGR 0418+5729 Fermi/GBM Detection of Pulsations
  7. GRB 090602: Suzaku WAM observation of the prompt emission
  8. RXTE Discovery of Pulsations from SGR 0418+5729
  9. GRB 090531B: Fermi GBM detection
  10. Discovery of a new soft gamma repeater source, SGR 0418+5729
  11. GRB 090608: Fermi GBM detection
  12. GRB 090606: Fermi GBM detection
  13. GRB 090530B: Suzaku WAM observation of the prompt emission
  14. GRB 090602: Fermi GBM detection
  15. GRB 090528: Suzaku WAM observation of the prompt emission
  16. GRB 090528B: Suzaku WAM observation of the prompt emission
  17. GRB090529B: ROVOR Upper Limits
  18. GRB 090529C: Fermi GBM detection
  19. GRB 090529B: Fermi GBM detection
  20. GRB 090530B: Fermi GBM detection
  21. GRB 090528B: MASTER-II Kourovka optical limit
  22. GRB 090528B: Fermi GBM detection
  23. GRB 090528: Fermi GBM detection
  24. GRB 090520D: Fermi GBM detection
  25. GRB 090520C: Fermi GBM detection
  26. GRB 090520B: Fermi GBM detection
  27. GRB090518B optical limit by "Pi of the Sky"
  28. GRB 090522 : Fermi GBM detection
  29. GRB 090524: Fermi GBM detection
  30. GRB 090513B: Fermi GBM detection
  31. GRB 090518: Fermi GBM detection
  32. GRB 090516C: Fermi GBM detection
  33. GRB 090423: Fermi GBM T90 follow-up analysis results
  34. GRB 090516: Fermi GBM observation
  35. GRB 090516B: Fermi GBM detection
  36. GRB 090519B: Fermi GBM detection
  37. GRB 090511: Fermi GBM Detection
  38. GRB 090514: Fermi GBM detection
  39. GRB 090518B: Fermi GBM detection
  40. GRB090513: Fermi GBM detection
  41. GRB 090509: Fermi GBM observation
  42. GRB 090510: Suzaku WAM observation of the prompt emission
  43. GRB 090510, Radio limits
  44. GRB090510: VLT/FORS2 spectroscopic redshift
  45. GRB 090510: GROND observations
  46. GRB 090510: Fermi-LAT follow-up analysis
  47. Fermi Gamma-ray Burst Monitor trigger 263649437 is not a GRB
  48. GRB 090510B: Fermi GBM detection
  49. GRB 090502: Fermi GBM detection
  50. Konus-Wind observation of GRB 090510
  51. GRB 090510: NOT afterglow confirmation
  52. GRB 090510: Fermi GBM detection
  53. Fermi LAT detection of GRB 090510
  54. GRB 090323: optical observations
  55. GRB 090428B: Suzaku WAM observation of the prompt emission
  56. GRB 090429D: Fermi GBM detection
  57. GRB 090429C: Fermi GBM detection
  58. GRB 090427C: Fermi GBM detection
  59. GRB 090427B: Fermi GBM detection
  60. GRB 090426C: Fermi GBM detection
  61. GRB 090426B: Fermi GBM detection/observation
  62. GRB 090428B: Fermi GBM detection
  63. GRB 090428: Fermi GBM detection
  64. GRB 090425: Fermi GBM detection
  65. GRB 090424: MASTER-Net prompt optical limit
  66. GRB 090423: Fermi GBM observation (correction of isotropic equivalent energy)
  67. GRB 090423: Swift/BAT spectral lag results
  68. GRB 090423: energetic, luminosity and jet break
  69. GRB 090424: Fermi GBM Observation
  70. GRB 090423: Fermi GBM observation
  71. GRB 090422: Fermi GBM observation
  72. GRB 090418C: Fermi GBM Detection
  73. GRB 090411B: Suzaku WAM observation of the prompt emission
  74. GRB 090411A: Suzaku WAM observation of the prompt emission
  75. GRB 090412: Fermi GBM detection
  76. GRB 090411B: Fermi GBM detection
  77. GRB 090411A: Fermi GBM detection
  78. Fermi GBM trigger 261106787 is not a GRB
  79. GRB 090409: Fermi GBM detection
  80. Fermi GBM Detection of a weak source
  81. GRB 090405: Fermi GBM Detection
  82. GRB 090403: Fermi GBM detection
  83. Fermi Gamma-ray Burst Monitor trigger 260428446 is not a GRB
  84. GRB 090328: Fermi-LAT refined analysis
  85. GRB 090331: Fermi GBM detection
  86. GRB 090328B: MASTER-Irkutsk prompt optical short burst observations
  87. GRB 090323: Further TLS detections - a break?
  88. GRB 090328: Radio afterglow detection
  89. GRB 090326: Fermi GBM detection
  90. GRB 090328: BOOTES-3 optical observations
  91. GRB 090328: Fermi GBM Spectral Analysis
  92. GRB 090328B: Fermi GBM Detection
  93. GRB 090330: Fermi GBM detection
  94. GRB 090328: GROND Detection of the Optical/NIR Afterglow
  95. GRB 090328: Gemini South Redshift
  96. GRB 090328: Swift XRT refined analysis
  97. Konus-Wind observation of GRB 090328
  98. GRB 090328: IPN Triangulation
  99. GRB 090328: Swift UVOT observations
  100. Fermi LAT and GBM detections of GRB090328

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