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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"

27330 results found.

  1. GRB 230308A: CALET Gamma-Ray Burst Monitor detection
  2. Trigger 1159327: Swift detection of SGR1806-20
  3. GRB 230307A: MAXI/GSC upper limit
  4. GRB 230307A: Gemini-South Confirmation of the Optical Afterglow
  5. Fermi GRB 230310A: Global MASTER-Net observations report
  6. GRB 230310A: Fermi GBM Final Real-time Localization
  7. GRB 230307A: ATLAS information on the ULTRACAM optical afterglow candidate
  8. GRB 230204B: MASTER detection of an object near NTT Optical Afterglow Candidate
  9. GRB 230308A: Fermi GBM detection
  10. GRB 230307A: ASO-S/HXI detection
  11. GRB 230228A: NUTTelA-TAO / BSTI Optical Limits
  12. Swift Trigger 1159108 is not a GRB
  13. GRB 230307A: Upper limits from a neutrino search with IceCube
  14. Fermi GRB 230307A: Global MASTER-Net observations report
  15. GRB 230304B: CALET Gamma-Ray Burst Monitor detection
  16. Fermi GRB 230308A: Global MASTER-Net observations report
  17. GRB 230308A: BALROG localization (Fermi Trigger 699975152 / GRB 230308564)
  18. GRB 230308A: Fermi GBM Final Real-time Localization
  19. GRB 230305A: Detection by GRBAlpha
  20. GRB 230307A: BALROG localization (Fermi Trigger 699896651/ GRB 230307656)
  21. IPN triangulation of GRB 230307A (long/very bright)
  22. GRB 230307A: Fermi GBM Observation of a very bright burst
  23. GRB 230307A: Fermi GBM detection of a very bright GRB
  24. GRB 230307A: GECAM detection of an extremely bright burst
  25. GRB 230307A: Fermi GBM Final Real-time Localization
  26. Fermi trigger No 699811746: Global MASTER-Net observations report
  27. IceCube Alert 230306.46: Global MASTER-Net observations report
  28. GRB 230304B: Detection by GRBAlpha
  29. GRB 230304C: Fermi GBM Final Real-time Localization
  30. GRB 230304B: Fermi GBM Final Real-time Localization
  31. GRB 230304A: Fermi GBM Final Real-time Localization
  32. GRB 230228A: Swift-BAT refined analysis
  33. GRB 230228A: Swift/UVOT Upper Limits
  34. Fermi GRB 230301B: Global MASTER-Net observations report
  35. GRB 230301B: Fermi GBM Final Real-time Localization
  36. GRB 230228A: Fermi GBM Observation
  37. Fermi trigger No 699294715: Global MASTER-Net observations report
  38. Fermi trigger No 699311646: Global MASTER-Net observations report
  39. GRB 230301A: Fermi GBM Final Real-time Localization
  40. GRB 230228A: Swift-XRT refined Analysis
  41. GRB 230228A: Nanshan/NEXT optical upper limit
  42. GRB 230228A: Swift detection of a possibly short burst
  43. Fermi GRB 230227A: Global MASTER-Net observations report
  44. GRB 230227A: Fermi GBM Final Real-time Localization
  45. Fermi trigger No 699029364: Global MASTER-Net observations report
  46. GRB 230217A: Swift/UVOT Upper Limits
  47. GRB 230216A: Swift/UVOT Upper Limits
  48. GRB 230217A: Continued Gemini Observations
  49. GRB 230222A: Fermi GBM Final Real-time Localization
  50. GRB 230217A: Swift-BAT refined analysis
  51. Fermi GRB 230220B: Global MASTER-Net observations report
  52. GRB 230216B: CALET Gamma-Ray Burst Monitor detection
  53. GRB 230220B: Fermi GBM Final Real-time Localization
  54. GRB 230217A: Gemini-South Optical Observation
  55. GRB 230217A: Fermi GBM observation
  56. Fermi trigger No 698427992: Global MASTER-Net observations report
  57. IceCube Alert 230217.87: Global MASTER-Net observations report
  58. GRB 230218A is not a GRB
  59. GRB 230218A: Fermi GBM Final Real-time Localization
  60. GRB 230207B: CALET Gamma-Ray Burst Monitor detection
  61. GRB 230216A: SVOM/C-GFT optical upper limit
  62. GRB 230217A: Swift detection of a short burst
  63. GRB 230217A: Fermi GBM Final Real-time Localization
  64. GRB 230216A: Swift-BAT refined analysis
  65. GRB 230216A: Swift-XRT refined Analysis
  66. Swift GRB 230216A: Global MASTER-Net observations report
  67. GRB 230216A: AKO Upper Limit
  68. GRB 230216A: Zadko observatory - Gingin optical observations
  69. GRB 230216A: Swift detection of a burst
  70. Fermi GRB 230215A: Global MASTER-Net observations report
  71. GRB 230215A: Fermi GBM Final Real-time Localization
  72. GRB 230209B: Fermi GBM Observation
  73. IPN triangulation of GRB 230209B
  74. GRB 230204B: CALET Gamma-Ray Burst Monitor detection
  75. GRB 230204B: ATCA radio detection
  76. Outburst from LS V +44 17 / RX J0440.9+4431: Transient detection by GRBAlpha
  77. Fermi trigger No 697926015: Global MASTER-Net observations report
  78. Fermi trigger No 697904388: Global MASTER-Net observations report
  79. 230211A is not a GRB
  80. GRB 230211A: Fermi GBM Final Real-time Localization
  81. GRB 230209B: Swift/BAT-GUANO detection outside the coded FOV
  82. Fermi trigger No 697678542: Global MASTER-Net observations report
  83. Swift Trigger 1153670 is probably not a GRB
  84. GRB 230210A: Fermi GBM Final Real-time Localization
  85. Fermi GRB 230209B: Global MASTER-Net observations report
  86. GRB 230209B: Fermi GBM Final Real-time Localization
  87. GRB 230209A is not a GRB
  88. GRB 230209A: Fermi GBM Final Real-time Localization
  89. GRB 221009A: Continued Swift Observations
  90. Fermi Gamma-ray Burst Monitor trigger 230208382/697540213 is not a GRB
  91. GRB 230207B: Detection by GRBAlpha
  92. GRB 230204B: MASTER early OT detection
  93. GRB 230208A: Fermi GBM Final Real-time Localization
  94. Fermi Gamma-ray Burst Monitor triggers 230206723/697396830 and 230206797/697403223 are not GRBs
  95. GRB 230207B: Swift/BAT-GUANO detection outside the coded FOV
  96. Fermi GRB 230207A: Global MASTER-Net observations report
  97. GRB 230207A: Fermi GBM Final Real-time Localization
  98. GRB 230204B: LCOGT Optical Upper Limits
  99. GRB 230204B: Swift/UVOT Upper Limits
  100. Fermi trigger No 697403223: Global MASTER-Net observations report

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