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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"

14992 results found.

  1. GRB 210420B: BOOTES-4/MET optical afterglow detection
  2. GRB 210420B: MASTER optical counterpart detection
  3. GRB 210420B: Swift detection of a burst
  4. GRB 210419C: Montarrenti Observatory Upper Limit
  5. GRB 210420A: Fermi GBM Final Real-time Localization
  6. GRB 210419C: Swift detection of a burst
  7. GRB 210419B: Fermi GBM Final Real-time Localization
  8. GRB 210419A: Swift detection of a burst
  9. GRB 210413B: Swift/BAT detection and probable localization of a short burst
  10. GRB 210411B: AstroSat CZTI detection
  11. GRB 210410A: AstroSat CZTI detection
  12. GRB 210410A: A twin of short GRB 090510 with complementary observations
  13. GRB 210415A: Fermi GBM Final Real-time Localization
  14. GRB 210413A: GECAM detection
  15. GRB 210411C: Swift/UVOT Detection
  16. GRB 210411C: VLT/X-shooter redshift
  17. GRB 210411C: BOOTES-4/MET optical upper limit
  18. GRB 210411C: LCO Optical Afterglow Candidate
  19. GRB 210406A: 10.4m GTC follow-up observation
  20. Konus-Wind detection of GRB 210410A
  21. GRB 210411D: Fermi GBM Final Real-time Localization
  22. GRB 210411C: Swift detection of a burst with an optical counterpart
  23. GRB 210411B: Fermi GBM Final Real-time Localization
  24. GRB 210411A: Fermi GBM Final Real-time Localization
  25. GRB 210410A: Fermi GBM detection
  26. GRB 210409A: GECAM detection
  27. GRB 210410A: AGILE detection of a burst
  28. GRB 210410A: Fermi-LAT detection
  29. GRB 210410A: Fermi GBM Final Real-time Localization
  30. GRB 210406B: Fermi GBM detection
  31. Konus-Wind detection of GRB 210406A
  32. GRB 210406A: Fermi GBM detection
  33. GRB 210406A: Konkoly Obs. optical upper limit
  34. GRB 210406A: BOOTES-4/MET optical upper limit
  35. GRB 210402A: Fermi GBM detection
  36. GRB 210207B: Prompt and very late time observations with HCT.
  37. GRB 210401A: GECAM detection
  38. GRB 210402A: BOOTES-network early optical upper limit
  39. GRB 210402A: DDOTI Upper Limits
  40. GRB 210330A: AstroSat CZTI detection
  41. GRB 210403A: Swift detection of a burst
  42. GRB 210328A: AstroSat CZTI detection
  43. Konus-Wind detection of GRB 210401A
  44. GRB 210402A: Swift detection of a burst
  45. GRB 210401A: Fermi GBM Final Real-time Localization
  46. GRB 210328A: GECAM detection
  47. GRB 210330A: GECAM detection
  48. GRB 210324A: AstroSat CZTI detection
  49. GRB 210324C: AstroSat CZTI detection
  50. GRB 210328A: Fermi GBM Final Real-time Localization
  51. GRB 210326A: Insight-HXMT/HE detection
  52. GRB 210326A: Fermi GBM Final Localization
  53. Konus-Wind detection of GRB 210324C
  54. IPN triangulation of GRB 210324C
  55. GRB 210323A: Insight-HXMT/HE detection
  56. GRB 210321A: OSN Upper Limit
  57. GRB 210323A: MASTER optical observation
  58. GRB 210323A: Gemini-North Optical Source Detection
  59. GRB 210324C: Fermi GBM Final Real-time Localization
  60. Short GRB 210323A: GTC Observations
  61. GRB 210312B: OSN Afterglow Observations
  62. GRB 210324B: Fermi GBM Final Real-time Localization
  63. Konus-Wind detection of GRB 210323A (short)
  64. GRB 210323A: Kitab optical upper limit
  65. GRB 210323A: Fermi GBM detection
  66. GRB 210323A: Mondy optical observations, counterpart detection
  67. GRB 210324A: Fermi GBM Final Real-time Localization
  68. GRB 210323B: Swift/BAT-GUANO detection and possible arcminute localization
  69. GRB 210323A: Swift detection of a short burst
  70. GRB 210321A: Swift/UVOT Detection
  71. Konus-Wind detection of GRB 210321A
  72. IceCube Astrotrack Bronze 135113_19489408.amon is likely background
  73. GRB 210321A: NOT optical afterglow detection and redshift limit
  74. GRB 210321A: Swift/UVOT Detection
  75. GRB 210321A: Swift detection of a burst
  76. GRB 210320A: MAXI/GSC detection
  77. GRB 210318B: Fermi GBM detection
  78. Konus-Wind detection of GRB 210318B
  79. GRB210318B: Swift detection of a burst
  80. GRB 210318A: Swift detection of a burst
  81. GRB 210317A: GECAM detection
  82. GRB 210317A: Fermi GBM Final Real-time Localization
  83. GRB 210312A: Fermi GBM Final Real-time Localization
  84. Konus-Wind detection of GRB 210308A
  85. Konus-Wind detection of GRB 210306A
  86. Konus-Wind detection of GRB 210305A
  87. GRB 210306A: Early Spectroscopy of the Optical Afterglow
  88. GRB 210306B: Fermi GBM detection
  89. GRB 210306A: Swift/UVOT Detection
  90. GRB 210308A: Swift/UVOT Detection
  91. GRB 210308A: Fermi GBM detection
  92. GRB 210308A: Swift detection of a burst with an optical counterpart
  93. GRB 210307B: GECAM detection
  94. GRB 210307A: LCO Optical Upper Limits
  95. GRB 210307A: Swift detection of a burst
  96. GRB 210306A: Fermi-LAT detection
  97. GRB 210306B: Swift detection of a burst
  98. GRB 210306A: LCO Optical Afterglow Detection
  99. GRB 210306A: Swift detection of a burst with a bright optical counterpart
  100. GRB 210305A: Swift detection of a burst

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