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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"

14983 results found.

  1. SGR 1830-0645: pre-discovery detection in Swift/BAT
  2. SGR 1830-0645 / GRB 201010A: 1.5m OSN optical upper limit
  3. SGR 1830-0645 / GRB 201010A: Kitab optical non-detection
  4. Swift detection of a new SGR 1830-0645 or a short GRB 201010A
  5. IceCube-201007A: No significant detection in HAWC
  6. GRB 201008B: Fermi GBM Final Localization
  7. GRB 201009A: AstroSat CZTI detection
  8. GRB 201009A: AGILE detection of a burst
  9. IceCube-200926A: Upper limits from Insight-HXMT Observations
  10. GRB 201008A: Swift/BAT-GUANO detection and possible arcminute localization
  11. IceCube-201007A - IceCube observation of a high-energy neutrino candidate track-like event
  12. GRB 201006A: GROWTH-India Telescope optical upper limit
  13. GRB 201007A: Fermi GBM Final Real-time Localization
  14. GRB 201006A: Fermi GBM detection
  15. INTEGRAL sub-threshold detection of GRB 201006A
  16. GRB 201006A: Swift detection of a burst
  17. GRB 201004A: Fermi GBM Final Localization
  18. IceCube-200929A: No significant detection in HAWC
  19. GRB 201001A: Swift detection of a burst
  20. GRB 201001A: Fermi GBM Final Real-time Localization
  21. IceCube-200929A: No neutrino counterpart candidates in ANTARES search
  22. IceCube-200926B: No significant detection in HAWC
  23. GRB 200928B: Insight-HXMT/HE detection
  24. IceCube-200929A: IceCube observation of a high-energy neutrino candidate event
  25. IceCube-200926A: No significant detection in HAWC
  26. GRB 200928B: AstroSat CZTI detection
  27. GRB 200929A: Fermi GBM Final Real-time Localization
  28. GRB 200928B: Fermi GBM Final Real-time Localization
  29. GRB 200928A: Fermi GBM Final Localization
  30. IceCube-200926B: No neutrino counterpart candidates in ANTARES search
  31. Swift-XRT observations of IceCube 200926A
  32. Konus-Wind detection of GRB 200920B
  33. GRB 200925B NUTTelA-TAO / BSTI Early Measurements (Preliminary)
  34. IceCube-200926B: IceCube observation of a high-energy neutrino candidate event
  35. GRB 200925B: Swift/UVOT Detection
  36. IceCube-200926A: IceCube observation of a high-energy neutrino candidate event
  37. Swift GRB 200925B: Global MASTER-Net OT detection
  38. GRB 200925B: Swift detection of a burst
  39. GRB 200925A: Fermi GBM Final Real-time Localization
  40. Konus-Wind observation of GRB 200914A
  41. GRB 200924B: Fermi GBM Final Localization
  42. GRB 200922A: Insight-HXMT/HE detection
  43. GRB 200924A: Fermi GBM Final Real-time Localization
  44. GRB 200923A: Fermi GBM Final Real-time Localization
  45. GRB 200922A: Swift/UVOT Detection
  46. Fermi-LAT Gamma-ray Observations of IceCube-200921A and detection of a new gamma-ray source, Fermi J1256.9+2630
  47. IceCube-200921A: no significant detection in HAWC observations
  48. GRB 200922B: Fermi GBM Final Real-time Localization
  49. GRB 200919C: Insight-HXMT/HE detection
  50. GRB 200922A: Swift detection of a burst with possible optical counterpart
  51. IceCube-200921A: IceCube observation of a high-energy neutrino candidate event
  52. IPN triangulation of GRB 200920B (short)
  53. GRB 200920B: AGILE/MCAL detection of a burst
  54. GRB 200920A: Fermi GBM Final Real-time Localization
  55. GRB 200919C: Fermi GBM Final Real-time Localization
  56. GRB 200919B: Fermi GBM Final Real-time Localization
  57. GRB 200919A: Swift detection of a burst
  58. GRB 200916B: AstroSat CZTI detection
  59. GRB 200917A: GROWTH-India Telescope optical upper limit.
  60. IceCube-200916A: No significant detection in HAWC
  61. IceCube-200916A: No neutrino counterpart candidates in ANTARES search
  62. Fermi-GBM Sub-Threshold Detection of GRB 200917A
  63. GRB 200917A: Swift detection of a burst
  64. IceCube-200916A - IceCube observation of a high-energy neutrino candidate track-like event
  65. GRB 200916A: Fermi GBM Final Real-time Localization
  66. GRB 200914A: AGILE detection
  67. IceCube-200911A: No significant detection in HAWC
  68. Fermi-LAT Gamma-ray Observations of IceCube-200911A and detection of a new gamma-ray source, Fermi J0330.1+3743
  69. GRB 200914A: Fermi GBM Final Real-time Localization
  70. IceCube-200911A: No neutrino counterpart candidates in ANTARES search
  71. IceCube-200911A: IceCube observation of a high-energy neutrino candidate event
  72. GRB 200826A: uGMRT radio upper limit at 1.25 GHz
  73. IPN triangulation of GRB 200907A (short)
  74. GRB 200909B: Swift detection of a burst
  75. GRB 200909A: AstroSat CZTI detection
  76. GRB 200909A: Fermi GBM Final Real-time Localization
  77. Konus-Wind detection of GRB 200903E
  78. GRB 200908A: Fermi GBM Final Real-time Localization
  79. GRB 200907B: AstroSat CZTI detection
  80. GRB 200907C: Fermi GBM Final Real-time Localization
  81. Correction to GCN 28387: GRB 200907B GROWTH-India optical upper limit
  82. GRB200907A: GROWTH-India optical upper limit
  83. GRB 200907B: Swift detection of a short burst
  84. IPN triangulation of GRB 200903E
  85. GRB 200906A: EMIR/GTC NIR upper limit
  86. GRB 200907A: AGILE/MCAL detection of a burst
  87. GRB 200906A: GROWTH-India Telescope (GIT) optical r band upper limit
  88. GRB 200906A: OSN 1.5m Upper Limit
  89. GRB 200906A: Fermi GBM detection
  90. GRB 200906A: Swift detection of a burst
  91. GRB 200906A: Fermi GBM Final Real-time Localization
  92. GRB 200903E: AstroSat CZTI detection
  93. GRB 200904A: Fermi GBM Final Real-time Localization
  94. GRB 200903D: MAXI/GSC detection
  95. GRB 200903A: Fermi GBM detection
  96. GRB 200903C: Fermi GBM Final Real-time Localization
  97. GRB 200903B: Insight-HXMT/HE detection
  98. GRB 200903A: CALET Gamma-Ray Burst Monitor detection
  99. AGILE detection of a burst (AGILE trigger no. 526185273)
  100. ZTF20abtxwfx/AT2020sev : AstroSat CZTI non-detection of a transient

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