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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"

14986 results found.

  1. GRB 201221D: Swift detection of a bright short burst
  2. correction to GCN 29110 - Fermi GBM Sub-Threshold Detection of GRB 201221A
  3. Fermi GBM Sub-Threshold Detection of GRB 201221A
  4. IceCube-201221A: IceCube observation of a high-energy neutrino candidate event
  5. GRB 201221B: Fermi GBM Final Real-time Localization
  6. GRB 201221A: Swift detection of a burst
  7. Konus-Wind observation of GRB 201218A
  8. GRB 201209A: Mondy optical observations, afterglow confirmation
  9. GRB 201214A: Swift-XRT afterglow detection
  10. IPN triangulation of GRB 201218A
  11. GRB 201218B: Fermi GBM Final Real-time Localization
  12. GRB201216C: No significant detection in HAWC
  13. Konus-Wind detection of GRB 201216C
  14. IceCube-201209A : MAXI/GSC upper limit
  15. GRB 201218A: Fermi GBM Final Real-time Localization
  16. GRB 201217A: Fermi GBM Final Localization
  17. GRB 201216C: VLT X-shooter spectroscopy and potential high redshift of a VHE-emitting GRB
  18. GRB 201216C: MAGIC detection in very high energy gamma rays
  19. GRB 201216C: AstroSat CZTI detection
  20. GRB 201216C: Fermi GBM detection
  21. GRB 201216A: Fermi GBM detection
  22. GRB 201216C: Fermi GBM Final Real-time Localization
  23. GRB 201216C: Swift detection of a burst
  24. GRB 201216A: Swift/BAT-GUANO detection and arcminute localization
  25. GRB 201216B: AGILE detection of a burst
  26. GRB 201216A: Fermi GBM Final Real-time Localization
  27. Chandra observations of GW170817 at ~3.3 years since merger (Full report)
  28. GRB 201209A: Insight-HXMT/HE detection
  29. IceCube-201209A: Upper limits from Insight-HXMT/HE observations
  30. GRB 201215A: Fermi GBM Final Real-time Localization
  31. GRB 201214B: Swift BAT location of short burst
  32. IceCube-201209: No significant detection in HAWC
  33. GRB 201214A: Mates' birthday GRB optical limit from FRAM-ORM
  34. GRB 201214B: Fermi GBM Final Real-time Localization
  35. GRB 201213A: Fermi GBM Final Real-time Localization
  36. GRB 200826A: GMOS-N detected source magnitude (Correction)
  37. GRB 201015A: 5-GHz radio afterglow detection with the EVN
  38. IceCube-201209A: No neutrino counterpart candidates in ANTARES search
  39. IPN triangulation of GRB 201207A
  40. GRB 201208A: Swift-XRT afterglow detection
  41. GRB 201209A: Xinglong-2.16m likely optical afterglow detection
  42. IceCube-201209A: IceCube observation of a high-energy neutrino candidate event
  43. GRB 201209A: AstroSat CZTI detection
  44. GRB 201207A: AGILE detection
  45. IceCube-201130A: Optical and NIR Imaging Follow-up by Kanata Telescope
  46. GRB 201209A: Swift detection of a burst
  47. GRB 201208A: Fermi-LAT detection
  48. GRB 201208A: AstroSat CZTI detection
  49. GRB 201207A: AstroSat CZTI detection
  50. GRB 201208A: Fermi GBM Final Real-time Localization
  51. GRB 201207A: Fermi GBM Final Real-time Localization
  52. GRB 201203A: Swift-XRT afterglow detection
  53. GRB 201203A: KAIT Optical Upper Limit
  54. GRB 201203A: DDOTI Observations
  55. GRB 201203A: Swift detection of a burst
  56. IceCube-201130A: No significant detection in HAWC
  57. GRB201130A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 628407054)
  58. GRB 201201A: Fermi GBM Final Real-time Localization
  59. GRB 201128B: Swift/BAT-GUANO detection and arcminute localization
  60. IceCube-201130A: IceCube observation of a high-energy neutrino candidate event
  61. GRB 201130A: Fermi GBM Final Real-time Localization
  62. GRB 201128A: Swift detection of a burst
  63. GRB 201121A: Insight-HXMT/HE detection
  64. AMON IC_HAWC NuEm-201124A: No Neutrino Counterpart detected with ANTARES
  65. IceCube-201120A in the Cygnus region: No enhanced TeV gamma-ray flux detected by HAWC
  66. GRB 200826A: TNG and LBT constraints on a supernova bump
  67. GRB 201122A: Insight-HXMT/HE detection
  68. IceCube-201114A: DECam observations and candidate optical counterpart
  69. GRB 201015A L-band observations with e-MERLIN
  70. IceCube-201120A: Swift-XRT non-detection of 4FGL J2028.6+4110e
  71. GRB 201015A radio afterglow with e-MERLIN
  72. GRB 201121B: Fermi GBM Final Real-time Localization
  73. GRB 201121A: Fermi GBM Final Real-time Localization
  74. GRB 201120B: Fermi GBM Final Localization
  75. GRB 201120A: Fermi GBM Final Localization
  76. IceCube-201120A: IceCube observation of a high-energy neutrino candidate event
  77. GRB 201116A: CALET Gamma-Ray Burst Monitor detection
  78. Konus-Wind detection of GRB 201116A
  79. Trigger 1007266: Swift detection of 1A 0535+262
  80. GRB 201116A: Swift-XRT afterglow detection
  81. IceCube-201115A: No significant detection in HAWC
  82. IceCube-201114A: No significant detection in HAWC
  83. GRB 201116A: Fermi-LAT detection
  84. IceCube-201115A: No neutrino counterpart candidates in ANTARES search
  85. GRB 201116A: Fermi GBM Final Real-time Localization
  86. Swift XRT observations of the Fermi-LAT source 4FGL J0658.6+0636, positionally consistent with the IceCube high-energy neutrino alert
  87. VLASS identifies possible radio counterparts to IceCube-201115A, including a bright BL Lac candidate
  88. IceCube GCN alert 134701_49508272.amon retraction
  89. IceCube-201114A: No neutrino counterpart candidates in ANTARES search
  90. IceCube-201115A: IceCube observation of a high-energy neutrino candidate event
  91. IceCube-201114A - IceCube observation of a high-energy neutrino candidate event
  92. GRB 201114A: AstroSat CZTI detection
  93. Konus-Wind observation of GRB 201109A
  94. Swift Trigger 1005428: Detection of SGR 1830-0645
  95. GRB 201111A: Fermi GBM Final Real-time Localization
  96. IPN triangulation of GRB 201109A (short)
  97. GRB 201109A: Fermi GBM detection
  98. GRB 201104A: AstroSat CZTI detection
  99. Konus-Wind observation of GRB 201103B
  100. GRB 201109A: Fermi GBM Final Real-time Localization

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