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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"

3838 results found.

  1. Fermi GRB 220711B: Global MASTER-Net observations report
  2. GRB 220710A: Swift/BAT-GUANO arcminute localization
  3. GRB 220708A: Swift detection of a burst
  4. IceCube-220629A: Upper limits from a search for additional neutrino events in IceCube
  5. Fermi-LAT Gamma-ray Observations of IceCube-220629A
  6. IceCube-220629A: No significant detection in HAWC
  7. IceCube-220629A - IceCube observation of a high-energy neutrino candidate track-like event
  8. IceCube Alert 220629.99: Global MASTER-Net observations report
  9. Trigger 1113743: Swift detection of MAXI J0655-013
  10. Fermi GRB 220623B: Global MASTER-Net observations report
  11. IPN triangulation of GRB 220624A
  12. Fermi GRB 220620A: Global MASTER-Net observations report
  13. GRB 220617A: Swift-XRT observations
  14. GRB 220618A: Swift detection of a burst
  15. Konus-Wind detection of an intermediate flare from SGR 1935+2154 on June 16
  16. IPN triangulation of GRB 220606C
  17. Fermi trigger No 676909037: Global MASTER-Net observations report
  18. Fermi GRB 220610A: Global MASTER-Net observations report
  19. Fermi trigger No 676537486: Global MASTER-Net observations report
  20. Fermi trigger No 675992935: Global MASTER-Net observations report
  21. Trigger 1108538: Swift detection of a burst from SGR J1935+2154
  22. Fermi trigger No 675411172: Global MASTER-Net observations report
  23. Konus-Wind detection of a burst from SGR 1935+2154 on 2022 May 25
  24. IPN triangulation of GRB 220524B
  25. Konus-Wind detection of GRB 220521B
  26. IPN triangulation of GRB 220521B
  27. Fermi GRB 220523B: Global MASTER-Net observations report
  28. GRB 220523A: Fermi GBM Final Real-time Localization
  29. Fermi GRB 220522A: Global MASTER-Net observations report
  30. GRB 220514A: AstroSat CZTI detection
  31. Fermi GRB 220518B: Global MASTER-Net observations report
  32. IceCube Alert 220513.97: Global MASTER-Net observations report
  33. Fermi GRB 220513A: Global MASTER-Net observations report
  34. IceCube-220509A: No significant detection in HAWC
  35. Fermi trigger No 673846271: Global MASTER-Net observations report
  36. MAXI GRB220506.27: Global MASTER-Net observations report
  37. IPN triangulation of GRB 220423A
  38. Fermi GRB 220426A: Global MASTER-Net observations report
  39. Fermi trigger No 672374264: Global MASTER-Net observations report
  40. Fermi GRB 220417A: Global MASTER-Net observations report
  41. Fermi trigger No 671729344: Global MASTER-Net observations report
  42. GRB 220408B: Fermi GBM observation
  43. Fermi GRB 220411A: Global MASTER-Net observations report
  44. GRB 220408A: 1.3m DFOT Optical upper limit
  45. GRB 220408A: LOAO, DOAO, and, SAO optical upper limit
  46. GRB 220408A: Swift detection of a burst with an optical counterpart, possibly associated with M51
  47. IceCube Alert 220405.21: Global MASTER-Net observations report
  48. Swift GRB 220403B: Global MASTER-Net observations report
  49. Fermi GRB 220401B: Global MASTER-Net observations report
  50. GRB 220401B: Fermi GBM Final Real-time Localization
  51. Fermi GRB 220330A: Global MASTER-Net observations report
  52. Konus-Wind observation of GRB 220320A
  53. GRB 220325A: MASTER Global Robotic Net optical observations
  54. GRB 220310A: MAXI/GSC detection
  55. IceCube-220303A: No significant detection in HAWC
  56. Fermi GRB 220309A: Global MASTER-Net observations report
  57. Fermi trigger No 668410535: Global MASTER-Net observations report
  58. Fermi GRB 220306A: Global MASTER-Net observations report
  59. GRB 220305A: Swift detection of a burst
  60. IceCube Alert 220303.75: Global MASTER-Net observations report
  61. IceCube Alert 220225.59: Global MASTER-Net observations report
  62. ZTF22aabjpxh/AT2022cva (GRB 220219B): Mondy optical observations
  63. Fermi GRB 220222B: Global MASTER-Net observations report
  64. IceCube Alert 220220.60:NuEm-220220A: MASTER optical possible counterpart
  65. IceCube Alert 220220.60: Global MASTER-Net observations report
  66. Fermi trigger No 666962499: Global MASTER-Net observations report
  67. Swift GRB220218.94: Global MASTER-Net observations report
  68. GRB 220211A: redshift lower limit estimating
  69. IPN triangulation of GRB 220209A
  70. Fermi GBM trigger 666393834/220212892 is not a GRB
  71. GRB 220209A: GECAM detection
  72. GRB 220203A: GECAM detection
  73. GRB 220131B: GECAM detection
  74. GRB 220130A: GECAM detection
  75. GRB 220129A: Fermi GBM Final Real-time Localization
  76. GRB 220127A: GECAM detection
  77. GECAM observations of a series of bursts from SGR J1935+2154
  78. GRB 220124A: GECAM detection
  79. Fermi trigger No 664738369: Global MASTER-Net observations report
  80. GRB 220121B: GECAM detection
  81. AGILE observations of a bright burst from SGR 1935+2154
  82. Konus-Wind detection of an intermediate flare from SGR 1935+2154 on January 20
  83. IPN triangulation of a bright burst from SGR 1935+2154
  84. Konus-Wind observation of the recent SGR 1935+2154 activity
  85. GRB 220118A: MITSuME Akeno optical observation
  86. Swift GRB 220118A: Global MASTER-Net observations report
  87. GRB 220118A: Swift detection of a burst with an optical counterpart
  88. GECAM observations of a series of bursts from SGR J1935+2154
  89. Fermi trigger No 663966693: Global MASTER-Net observations report
  90. GECAM observations of a series of bursts from SGR J1935+2154
  91. Fermi-GBM Observations of Recent Bursting Activity from SGR J1935+2154
  92. AGILE observations of a burst from SGR 1935+2154
  93. GECAM observations of a series of bursts from SGR J1935+2154
  94. Fermi Gamma-ray Burst Monitor trigger 220111325/663580106 is not a GRB
  95. GECAM observations of a series of bursts from SGR J1935+2154
  96. GECAM observation of a burst from SGR J1555.2-5402
  97. GECAM detection of a short burst from SGR 1935+2154
  98. Fermi trigger No 663129379: Global MASTER-Net observations report
  99. GECAM observations of a series of bursts from SGR J1935+2154
  100. GRB 220101A: iTelescope optical observations

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