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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"

11525 results found.

  1. GRB 201016A: Fermi GBM detection
  2. Fermi GRB 201016B: Global MASTER-Net observations report
  3. GRB 201016B: BALROG localization (Fermi Trigger 624510986 / GRB 201016136)
  4. GRB 201016A: BALROG localization (Fermi Trigger 624500874 / GRB 201016019)
  5. GRB 201016B: Fermi GBM Final Real-time Localization
  6. GRB 201016A: Fermi GBM Final Real-time Localization
  7. Fermi-LAT Gamma-ray Observations of IceCube-201014A
  8. IceCube-201014A: Not observable by GBM
  9. IceCube-201014A - IceCube observation of a high-energy neutrino candidate track-like event
  10. GRB 201011A: Fermi GBM detection of a likely Long GRB in the direction of SGR 1830-0645
  11. Fermi trigger No 624139481: AGILE detection
  12. GRB 201012A: Fermi GBM Final Real-time Localization
  13. Fermi trigger No 624139481: Global MASTER-Net observations report
  14. Fermi trigger No 624121589: Global MASTER-Net observations report
  15. GRB 201008B: Fermi GBM Final Localization
  16. GRB 201008A: Swift-XRT observations
  17. GRB 201008A: Swift ToO observations
  18. IceCube-201007A: Upper limits from Fermi-GBM Observations
  19. GRB 201008A: Swift/BAT-GUANO detection and possible arcminute localization
  20. Fermi-LAT Gamma-ray Observations of IceCube-201007A
  21. Fermi trigger No 623846261: Global MASTER-Net observations report
  22. Fermi trigger No 623873165: Global MASTER-Net observations report
  23. GRB 201008A: BALROG localization (Fermi Trigger 623846261 / GRB 201008443)
  24. IceCube-201007A - IceCube observation of a high-energy neutrino candidate track-like event
  25. Fermi GRB 201007A: Global MASTER-Net observations report
  26. GRB 201007A: Fermi GBM Final Real-time Localization
  27. GRB 201006A: Fermi GBM detection
  28. GRB 201006A is likely a short burst
  29. Fermi trigger No 623470566: Global MASTER-Net observations report
  30. GRB 201004A: Fermi GBM Final Localization
  31. Fermi trigger No 623493962: Global MASTER-Net observations report
  32. GRB 201001A: MITSuME Akeno optical upper limits
  33. GRB 201001A: Fermi GBM observation
  34. GRB 201001A: Fermi GBM Final Real-time Localization
  35. Fermi-LAT Gamma-ray Observations of IceCube-200929A
  36. IceCube-200929A: Upper limits from Fermi-GBM Observations
  37. GRB 200928B: Insight-HXMT/HE detection
  38. IceCube-200929A: IceCube observation of a high-energy neutrino candidate event
  39. IceCube-200926B: Upper limits from Fermi-GBM Observations
  40. IceCube-200926A: Upper limits from Fermi-GBM Observations
  41. Fermi GRB 200929A: Global MASTER-Net observations report
  42. GRB 200928B: AstroSat CZTI detection
  43. GRB 200929A: Fermi GBM Final Real-time Localization
  44. GRB 200928B: BALROG localization (Fermi Trigger 622991684 / GRB 200928552)
  45. GRB 200928B: Fermi GBM Final Real-time Localization
  46. Fermi-LAT Gamma-ray Observations of IceCube-200926B
  47. GRB 200928A: Fermi GBM Final Localization
  48. Fermi-LAT Gamma-ray Observations of IceCube-200926A
  49. IceCube-200926B: IceCube observation of a high-energy neutrino candidate event
  50. IceCube-200926A: IceCube observation of a high-energy neutrino candidate event
  51. Fermi GRB 200925A: Global MASTER-Net observations report
  52. GRB 200925A: Fermi GBM Final Real-time Localization
  53. Konus-Wind observation of GRB 200914A
  54. Fermi GRB 200924A: Global MASTER-Net observations report
  55. GRB 200924B: Fermi GBM Final Localization
  56. Fermi trigger No 622618714: Global MASTER-Net observations report
  57. GRB 200924A: Fermi GBM Final Real-time Localization
  58. Fermi GRB 200923A: Global MASTER-Net observations report
  59. GRB 200923A: Fermi GBM Final Real-time Localization
  60. Fermi-LAT Gamma-ray Observations of IceCube-200921A and detection of a new gamma-ray source, Fermi J1256.9+2630
  61. Fermi GRB 200922B: Global MASTER-Net observations report
  62. GRB 200922B: Fermi GBM Final Real-time Localization
  63. GRB 200919C: Insight-HXMT/HE detection
  64. IceCube-200921A: Upper limits from Fermi-GBM Observations
  65. IceCube-200921A: IceCube observation of a high-energy neutrino candidate event
  66. IPN triangulation of GRB 200920B (short)
  67. GRB 200920B: AGILE/MCAL detection of a burst
  68. GRB 200920A: Fermi GBM Final Real-time Localization
  69. Fermi GRB 200919C: Global MASTER-Net observations report
  70. GRB 200919C: Fermi GBM Final Real-time Localization
  71. Fermi GRB 200919B: Global MASTER-Net observations report
  72. GRB 200919B: Fermi GBM Final Real-time Localization
  73. Fermi-GBM Sub-Threshold Detection of GRB 200917A
  74. IceCube-200916A: Upper limits from Fermi-GBM Observations
  75. Fermi-LAT Gamma-ray Observations of IceCube-200916A
  76. IceCube-200916A - IceCube observation of a high-energy neutrino candidate track-like event
  77. Fermi GRB 200916A: Global MASTER-Net observations report
  78. GRB 200916A: Fermi GBM Final Real-time Localization
  79. Fermi trigger No 621893860: Global MASTER-Net observations report
  80. Fermi trigger No 621833240: Global MASTER-Net observations report
  81. Fermi GRB 200914A: Global MASTER-Net observations report
  82. GRB 200914A: AGILE detection
  83. GRB 200914A: Fermi GBM observation
  84. IceCube-200911A: No significant detection in HAWC
  85. Fermi-LAT Gamma-ray Observations of IceCube-200911A and detection of a new gamma-ray source, Fermi J0330.1+3743
  86. GRB 200914A: BALROG localization (Fermi Trigger 621780515 / GRB 200914534)
  87. GRB 200914A: Fermi GBM Final Real-time Localization
  88. IceCube-200911A: not observable by Fermi-GBM
  89. IceCube-200911A: IceCube observation of a high-energy neutrino candidate event
  90. GRB 200826A: uGMRT radio upper limit at 1.25 GHz
  91. GRB 200909A: AstroSat CZTI detection
  92. Fermi GRB 200909A: Global MASTER-Net observations report
  93. GRB 200909A: BALROG localization (Fermi Trigger 621316887 / GRB 200909168)
  94. GRB 200909A: Fermi GBM Final Real-time Localization
  95. Fermi GRB 200908A: Global MASTER-Net observations report
  96. GRB 200908A: Fermi GBM Final Real-time Localization
  97. Fermi GRB 200907C: Global MASTER-Net observations report
  98. GRB 200907C: Fermi GBM Final Real-time Localization
  99. Fermi GRB 200906A: Global MASTER-Net observations report
  100. GRB 200906A: EMIR/GTC NIR upper limit

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