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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"

36380 results found.

  1. Fermi Gamma-ray Burst Monitor trigger 230203275 / 697098930 is not a GRB
  2. GRB 221216A: Swift-BAT refined analysis
  3. Fermi GRB 230201B: Global MASTER-Net observations report
  4. GRB 230201B: Fermi GBM Final Real-time Localization
  5. GRB 230126A: Detection by VZLUSAT-2
  6. Fermi GRB 230201A: Global MASTER-Net observations report
  7. GRB 221009A: radio afterglow detection with the EVN
  8. GRB 230201A: Fermi GBM Final Real-time Localization
  9. ZTF23aaarlti/AT2023avj: Assy continued optical observations
  10. ZTF23aabmzlp/AT2023azs: Mondy and AbAO optical observations
  11. AT2023avj: X-ray Detection with Swift/XRT
  12. GRB 230129A: AstroSat CZTI detection
  13. GRB 230128A: AstroSat CZTI detection
  14. GRB 230130A: Fermi GBM Final Real-time Localization
  15. GRB 230129A: Fermi GBM Final Real-time Localization
  16. GRB 230128A: Fermi GBM Final Real-time Localization
  17. AT2023avj ZTF Candidate: Assy optical observations
  18. GRB 230126A: Fermi GBM Final Real-time Localization
  19. GRB 230124A: Fermi GBM Observation
  20. GRB 230124A: Swift/BAT-GUANO detection outside the coded FOV
  21. GRB 230114B: Detection by VZLUSAT-2
  22. GRB 230123A: LCOGT Optical Upper Limits
  23. Fermi GRB 230124A: Global MASTER-Net observations report
  24. GRB 230124A: Fermi GBM Final Real-time Localization
  25. GRB 230123A: Swift-BAT refined analysis
  26. GRB 230122A: Swift/BAT-GUANO detection
  27. GRB 230123A: Swift/UVOT Upper Limits
  28. GRB 230123A: Swift-XRT refined Analysis
  29. GRB 230123A: Enhanced Swift-XRT position
  30. GRB 230123A: Zadko observatory - Gingin optical observations
  31. GRB 230116C: Swift-XRT observations
  32. GRB 230123A: Swift detection of a burst
  33. GRB 230116B: Fermi GBM observation
  34. GRB 230120A: AstroSat CZTI detection
  35. IPN triangulation of GRB 230116B (short)
  36. GRB 230119A: CALET Gamma-Ray Burst Monitor detection
  37. GRB 230116D: 3.6m DOT optical upper limit
  38. GRB 230119A: Fermi GBM Final Real-time Localization
  39. Fermi GRB 230118A: Global MASTER-Net observations report
  40. GRB 230118A: Fermi GBM Final Real-time Localization
  41. GRB 230116D: Swift-BAT refined analysis
  42. GRB 230116C: Swift-BAT refined analysis
  43. GRB 230116D: SAO RAS further observations
  44. GRB 230116D: SAO RAS photometry
  45. GRB 230116D: KGO RC-25 optical observations
  46. GRB 230116D: Sintez-Newton/CrAO optical observations
  47. GRB 230116D: LCOGT Optical Upper Limit
  48. GRB 230116D: SAO RAS redshift
  49. GRB 230116D: Swift-XRT refined Analysis
  50. Fermi GRB 230117A: Global MASTER-Net observations report
  51. GRB 230117A: Fermi GBM Final Real-time Localization
  52. GRB 230116D: GIT optical follow-up
  53. GRB 230116D: GIT optical follow-up
  54. GRB 230116D: Enhanced Swift-XRT position
  55. GRB 230116D: SAO RAS observations of OT brightening
  56. GRB 230116D: Sintez-Newton/CrAO optical afterglow detection
  57. GRB 230116D: Nanshan/NEXT optical afterglow detection
  58. GRB 230116D: Swift detection of a burst
  59. GRB 230116C: Swift detection of a burst
  60. GRB 230116B: Fermi GBM Final Real-time Localization
  61. GRB 230116A: Fermi GBM Final Real-time Localization
  62. GRB 230114A: Detection by VZLUSAT-2
  63. GRB 230114A: Fermi GBM Final Real-time Localization
  64. GRB 230111A: Fermi GBM Observation
  65. Fermi GRB 230112A: Global MASTER-Net observations report
  66. GRB 230112A: Fermi GBM Final Real-time Localization
  67. GRB 230111A: MAXI/GSC detection
  68. GRB 230111A: Fermi GBM Final Real-time Localization
  69. GRB 230106: AstroSat LAXPC detection
  70. GRB 230102A: Fermi GBM Observation
  71. Fermi Gamma-ray Burst Monitor trigger 694043024/221229905 is not a GRB
  72. GRB 221231A: 3.6m DOT optical upper limit
  73. GRB 230104A: AGILE/MCAL detection of a burst
  74. GRB 230102A: Swift/BAT-GUANO detection outside the coded FOV
  75. GRB 221231A: Fermi GBM Observation
  76. GRB 221230A: CALET Gamma-Ray Burst Monitor detection
  77. Fermi Gamma-ray Burst Monitor trigger 694259491/230101411 is not a GRB
  78. GRB 230102A: Detection by GRBAlpha
  79. Fermi Gamma-ray Burst Monitor trigger 694302022/230101903 is not a GRB
  80. GRB 230101A: AstroSat CZTI detection
  81. GRB 221231A: Swift-XRT afterglow detection
  82. GRB 230102A: AGILE/MCAL detection
  83. GRB 230102A: Fermi GBM Final Real-time Localization
  84. GRB 221231A: AKO Upper Limit
  85. GRB 221231A: Swift-XRT observations
  86. GRB 221231A: Swift ToO observations
  87. GRB 221231A: Swift/BAT-GUANO arcminute localization of a possibly short burst
  88. GRB 230101A: Fermi GBM Final Real-time Localization
  89. GRB 221231A: Fermi GBM Final Real-time Localization
  90. GRB 221226A: Fermi GBM detection
  91. IPN triangulation of GRB 221226A
  92. GRB 221226A: Swift/BAT-GUANO detection outside the coded FOV
  93. GRB 221226B: LCOGT Optical Upper Limits
  94. GRB 221228A: Fermi GBM Final Real-time Localization
  95. GRB 221226B Swift-BAT refined analysis
  96. GRB 221226B: Swift-UVOT Detection
  97. GRB 221226A: AGILE detection
  98. GRB 221226B: Fermi GBM Observation
  99. GRB 221226B: Swift-XRT refined Analysis
  100. GRB 221226B: VLT/X-shooter redshift and host galaxy

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