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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"

11649 results found.

  1. GRB 201201A: Fermi GBM Final Real-time Localization
  2. GRB 201128B: Swift/BAT-GUANO detection and arcminute localization
  3. IceCube-201130A: IceCube observation of a high-energy neutrino candidate event
  4. GRB 201130A: DDOTI Observations
  5. Fermi GRB 201130A: Global MASTER-Net observations report
  6. GRB 201130A: Fermi GBM Final Real-time Localization
  7. Fermi trigger No 628278856: Global MASTER-Net observations report
  8. Fermi trigger No 628140709: DDOTI/OAN optical observations report
  9. Fermi trigger No 628140709: Global MASTER-Net observations report
  10. GRB 201121A: Insight-HXMT/HE detection
  11. GRB 200826A: TNG and LBT constraints on a supernova bump
  12. IceCube-201114A: DECam observations and candidate optical counterpart
  13. Fermi-LAT Gamma-ray Observations of IceCube-201120A
  14. Fermi trigger No 627645769: Global MASTER-Net observations report
  15. IceCube-201120A: Swift-XRT non-detection of 4FGL J2028.6+4110e
  16. Fermi GRB 201121A: Global MASTER-Net observations report
  17. GRB 201121B: Fermi GBM Final Real-time Localization
  18. GRB 201121A: BALROG localization (Fermi Trigger 627614994 / GRB 201121062)
  19. GRB 201121A: Fermi GBM Final Real-time Localization
  20. Fermi GRB 201120B: Global MASTER-Net observations report
  21. GRB 201120B: Fermi GBM Final Localization
  22. GRB 201120A: Fermi GBM Final Localization
  23. IceCube-201120A: Upper limits from Fermi-GBM Observations
  24. Fermi trigger No 627557935: Global MASTER-Net observations report
  25. IceCube-201120A: IceCube observation of a high-energy neutrino candidate event
  26. IceCube 201114A: Swift followup of Fermi J0703.5+0505
  27. GRB 201116A: CALET Gamma-Ray Burst Monitor detection
  28. Fermi trigger No 627438255: Global MASTER-Net observations report
  29. Konus-Wind detection of GRB 201116A
  30. Fermi-LAT Gamma-ray Observations of IceCube-201114A
  31. GRB 201116A: NOT optical observations
  32. GRB 201116A: Swift-XRT afterglow detection
  33. GRB 201116A: OSN Afterglow Candidate
  34. Fermi trigger No 627198169: Global MASTER-Net observations report
  35. IceCube-201114A: No significant detection in HAWC
  36. GRB 201116A: Fermi-LAT detection
  37. GRB 201116A: Tiled Swift observations
  38. Fermi-LAT Gamma-ray Observations of IceCube-201115A
  39. GRB 201116A: BALROG localization (Fermi Trigger 627180592 / GRB 201116035)
  40. GRB 201116A: Fermi GBM Final Real-time Localization
  41. IceCube-201115A: not observable by Fermi-GBM
  42. Swift XRT observations of the Fermi-LAT source 4FGL J0658.6+0636, positionally consistent with the IceCube high-energy neutrino alert
  43. IceCube-201114A: Upper limits from Fermi GBM Observations
  44. IceCube-201115A: IceCube observation of a high-energy neutrino candidate event
  45. IceCube-201114A - IceCube observation of a high-energy neutrino candidate event
  46. Fermi-LAT Gamma-ray Observations of NuEm-201107A
  47. Fermi GRB 201111A: Global MASTER-Net observations report
  48. Konus-Wind observation of GRB 201109A
  49. GRB 201111A: Fermi GBM Final Real-time Localization
  50. IPN triangulation of GRB 201109A (short)
  51. GRB 201109A: Fermi GBM detection
  52. GRB 201104A: AstroSat CZTI detection
  53. Fermi GRB 201109A: Global MASTER-Net observations report
  54. GRB 201109A: Fermi GBM Final Real-time Localization
  55. Fermi GRB 201108A: Global MASTER-Net observations report
  56. GRB 201108A: Fermi GBM Final Real-time Localization
  57. Konus-Wind detection of GRB 201105A
  58. GRB 201104A: Swift-XRT observations
  59. Correction to GCN 28843: GBM report of GRB 201105B should have been GRB 201105A
  60. Fermi trigger No 626247072: Global MASTER-Net observations report
  61. GRB 201105B: Fermi GBM observation
  62. GRB 201105A: BALROG localization (Fermi Trigger 626247072 / GRB 201105230)
  63. GRB 201104A: BALROG localization (Fermi Trigger 626140861 / GRB 201104001)
  64. GRB 201104C: Fermi GBM Final Real-time Localization
  65. GRB 201104A: Tiled Swift observations
  66. GRB 201104A: Fermi GBM observation
  67. GRB 201104A: AGILE/MCAL detection
  68. GRB 201104A: Fermi-LAT detection
  69. Fermi GRB 201104A: Global MASTER-Net observations report
  70. GRB 201104A: Fermi GBM Final Real-time Localization
  71. Fermi GRB 201103A: Global MASTER-Net observations report
  72. GRB 201103A: Fermi GBM Final Real-time Localization
  73. Fermi GRB 201031B: Global MASTER-Net observations report
  74. GRB 201031B: BALROG localization (Fermi Trigger 625859489 / GRB 201031744)
  75. GRB 201031B: Fermi GBM Final Real-time Localization
  76. IceCube 201021A: Swift follow-up of Fermi J1725.5+1312
  77. GRB 201029A: Fermi GBM detection
  78. Fermi trigger No 625695596: Global MASTER-Net observations report
  79. GRB 201026A: Fermi GBM detection
  80. GRB 201020B: 1.3m DFOT continued optical follow-up observations
  81. GRB 201020B: HCT and GIT continued optical follow-up observations
  82. GRB 201020B: follow-up observations with Savelli Telescope
  83. GRB 201020B: 1.3m DFOT optical observations
  84. GRB 201020B: follow-up observations at Konkoly
  85. GRB 201020B: continued Mondy optical observations
  86. GRB 201020B: Redshift from GTC/OSIRIS
  87. IceCube-201021A: Optical counterpart of WISEA J172314.13+142101.5
  88. GRB 201020B: GROWTH-India Telescope optical observations
  89. Fermi-LAT Gamma-ray Observations of IceCube-201021A and detection of a new gamma-ray source, Fermi J1725.5+1312
  90. GRB 201020B: Konkoly Obs. optical detection
  91. GRB 201021C: Fermi GBM detection
  92. Konus-Wind detection of GRB 201020A
  93. GRB 201020B: Swift/UVOT Detection
  94. GRB 201020B: Swift-XRT afterglow detection
  95. IceCube-201021A: Upper limits from Fermi-GBM Observations
  96. HAWC-201019A: not observable by Fermi-GBM
  97. GRB 201020B: Mondy optical observations
  98. Konus-Wind detection of GRB 201020B
  99. GRB 201020B: Swift ToO observations
  100. GRB 201020B: Nanshan/NEXT optical afterglow confirmation

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