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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 210419B: Fermi GBM Final Real-time Localization
  2. GRB 210419A: Swift detection of a burst
  3. GRB 210413B: Swift/BAT detection and probable localization of a short burst
  4. GRB 210411B: AstroSat CZTI detection
  5. GRB 210410A: AstroSat CZTI detection
  6. GRB 210410A: A twin of short GRB 090510 with complementary observations
  7. GRB 210415A: Fermi GBM Final Real-time Localization
  8. GRB 210413A: GECAM detection
  9. GRB 210411C: Swift/UVOT Detection
  10. GRB 210411C: VLT/X-shooter redshift
  11. GRB 210411C: BOOTES-4/MET optical upper limit
  12. GRB 210411C: LCO Optical Afterglow Candidate
  13. GRB 210406A: 10.4m GTC follow-up observation
  14. Konus-Wind detection of GRB 210410A
  15. GRB 210411D: Fermi GBM Final Real-time Localization
  16. GRB 210411C: Swift detection of a burst with an optical counterpart
  17. GRB 210411B: Fermi GBM Final Real-time Localization
  18. GRB 210411A: Fermi GBM Final Real-time Localization
  19. GRB 210410A: Fermi GBM detection
  20. GRB 210409A: GECAM detection
  21. GRB 210410A: AGILE detection of a burst
  22. GRB 210410A: Fermi-LAT detection
  23. GRB 210410A: Fermi GBM Final Real-time Localization
  24. GRB 210406B: Fermi GBM detection
  25. Konus-Wind detection of GRB 210406A
  26. GRB 210406A: Fermi GBM detection
  27. GRB 210406A: Konkoly Obs. optical upper limit
  28. GRB 210406A: BOOTES-4/MET optical upper limit
  29. GRB 210402A: Fermi GBM detection
  30. GRB 210207B: Prompt and very late time observations with HCT.
  31. GRB 210401A: GECAM detection
  32. GRB 210402A: BOOTES-network early optical upper limit
  33. GRB 210402A: DDOTI Upper Limits
  34. GRB 210330A: AstroSat CZTI detection
  35. GRB 210403A: Swift detection of a burst
  36. GRB 210328A: AstroSat CZTI detection
  37. Konus-Wind detection of GRB 210401A
  38. GRB 210402A: Swift detection of a burst
  39. GRB 210401A: Fermi GBM Final Real-time Localization
  40. GRB 210328A: GECAM detection
  41. GRB 210330A: GECAM detection
  42. GRB 210324A: AstroSat CZTI detection
  43. GRB 210324C: AstroSat CZTI detection
  44. GRB 210328A: Fermi GBM Final Real-time Localization
  45. GRB 210326A: Insight-HXMT/HE detection
  46. GRB 210326A: Fermi GBM Final Localization
  47. Konus-Wind detection of GRB 210324C
  48. IPN triangulation of GRB 210324C
  49. GRB 210323A: Insight-HXMT/HE detection
  50. GRB 210321A: OSN Upper Limit
  51. GRB 210323A: MASTER optical observation
  52. GRB 210323A: Gemini-North Optical Source Detection
  53. GRB 210324C: Fermi GBM Final Real-time Localization
  54. Short GRB 210323A: GTC Observations
  55. GRB 210312B: OSN Afterglow Observations
  56. GRB 210324B: Fermi GBM Final Real-time Localization
  57. Konus-Wind detection of GRB 210323A (short)
  58. GRB 210323A: Kitab optical upper limit
  59. GRB 210323A: Fermi GBM detection
  60. GRB 210323A: Mondy optical observations, counterpart detection
  61. GRB 210324A: Fermi GBM Final Real-time Localization
  62. GRB 210323B: Swift/BAT-GUANO detection and possible arcminute localization
  63. GRB 210323A: Swift detection of a short burst
  64. GRB 210321A: Swift/UVOT Detection
  65. Konus-Wind detection of GRB 210321A
  66. IceCube Astrotrack Bronze 135113_19489408.amon is likely background
  67. GRB 210321A: NOT optical afterglow detection and redshift limit
  68. GRB 210321A: Swift/UVOT Detection
  69. GRB 210321A: Swift detection of a burst
  70. GRB 210320A: MAXI/GSC detection
  71. GRB 210318B: Fermi GBM detection
  72. Konus-Wind detection of GRB 210318B
  73. GRB210318B: Swift detection of a burst
  74. GRB 210318A: Swift detection of a burst
  75. GRB 210317A: GECAM detection
  76. GRB 210317A: Fermi GBM Final Real-time Localization
  77. GRB 210312A: Fermi GBM Final Real-time Localization
  78. Konus-Wind detection of GRB 210308A
  79. Konus-Wind detection of GRB 210306A
  80. Konus-Wind detection of GRB 210305A
  81. GRB 210306A: Early Spectroscopy of the Optical Afterglow
  82. GRB 210306B: Fermi GBM detection
  83. GRB 210306A: Swift/UVOT Detection
  84. GRB 210308A: Swift/UVOT Detection
  85. GRB 210308A: Fermi GBM detection
  86. GRB 210308A: Swift detection of a burst with an optical counterpart
  87. GRB 210307B: GECAM detection
  88. GRB 210307A: LCO Optical Upper Limits
  89. GRB 210307A: Swift detection of a burst
  90. GRB 210306A: Fermi-LAT detection
  91. GRB 210306B: Swift detection of a burst
  92. GRB 210306A: LCO Optical Afterglow Detection
  93. GRB 210306A: Swift detection of a burst with a bright optical counterpart
  94. GRB 210305A: Swift detection of a burst
  95. GRB 210228B: Insight-HXMT/HE detection
  96. Trigger 1035744: Swift detection of Sco X-1 due to Star Tracker loss of lock
  97. GRB 210228A: GECAM detection
  98. Integral GRB210227.19: MASTER OT retraction
  99. GRB 210225A: Insight-HXMT/HE detection
  100. Integral GRB210227.19: Global MASTER-Net OT detection

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