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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"

39400 results found.

  1. GRB 230116D: Enhanced Swift-XRT position
  2. GRB 230116D: SAO RAS observations of OT brightening
  3. GRB 230116D: Sintez-Newton/CrAO optical afterglow detection
  4. GRB 230116D: Nanshan/NEXT optical afterglow detection
  5. GRB 230116D: Swift detection of a burst
  6. Swift GRB230116.88: Global MASTER-Net observations report
  7. GRB 230116C: Swift detection of a burst
  8. GRB 230116B: Fermi GBM Final Real-time Localization
  9. GRB 230116A: Fermi GBM Final Real-time Localization
  10. GRB 230114A: Detection by VZLUSAT-2
  11. Fermi-LAT gamma-ray observations of IceCube-230112A
  12. GRB 230114A: Fermi GBM Final Real-time Localization
  13. Fermi-LAT Gamma-ray Observations of IceCube-Cascade-230109A
  14. Fermi-LAT Gamma-ray Observations of IceCube-Cascade-221229A
  15. IceCube-230112A: BOOTES-4/MET Optical Upper Limit
  16. GRB 230111A: Fermi GBM Observation
  17. Fermi GRB 230112A: Global MASTER-Net observations report
  18. IceCube Alert 230112.28: Global MASTER-Net observations report
  19. GRB 230112A: Fermi GBM Final Real-time Localization
  20. GRB 230111A: MAXI/GSC detection
  21. GRB 230111A: Fermi GBM Final Real-time Localization
  22. GRB 230106: AstroSat LAXPC detection
  23. Fermi trigger No 695057654: Global MASTER-Net observations report
  24. GRB 230102A: Fermi GBM Observation
  25. Fermi Gamma-ray Burst Monitor trigger 694043024/221229905 is not a GRB
  26. GRB 221231A: 3.6m DOT optical upper limit
  27. GRB 230104A: AGILE/MCAL detection of a burst
  28. GRB 230102A: Swift/BAT-GUANO detection outside the coded FOV
  29. GRB 221231A: Fermi GBM Observation
  30. GRB 221230A: CALET Gamma-Ray Burst Monitor detection
  31. Fermi Gamma-ray Burst Monitor trigger 694259491/230101411 is not a GRB
  32. GRB 230102A: Detection by GRBAlpha
  33. Fermi Gamma-ray Burst Monitor trigger 694302022/230101903 is not a GRB
  34. GRB 230101A: AstroSat CZTI detection
  35. Fermi trigger No 694259491: Global MASTER-Net observations report
  36. GRB 221231A: Swift-XRT afterglow detection
  37. GRB 230102A: AGILE/MCAL detection
  38. GRB 230102A: Fermi GBM Final Real-time Localization
  39. GRB 221231A: AKO Upper Limit
  40. GRB 221231A: Swift-XRT observations
  41. GRB 221231A: Swift ToO observations
  42. GRB 221231A: Swift/BAT-GUANO arcminute localization of a possibly short burst
  43. Fermi trigger No 694232203: Global MASTER-Net observations report
  44. GRB 230101A: Fermi GBM Final Real-time Localization
  45. GRB 221231A: Fermi GBM Final Real-time Localization
  46. Fermi-LAT gamma-ray observations of IceCube-221229A
  47. GRB 221226A: Fermi GBM detection
  48. IPN triangulation of GRB 221226A
  49. GRB 221226A: Swift/BAT-GUANO detection outside the coded FOV
  50. ZTF22acaruqr/AT2022adzb: Neil Gehrels Swift Observatory X-ray detection
  51. GRB 221226B: LCOGT Optical Upper Limits
  52. GRB 221228A: Fermi GBM Final Real-time Localization
  53. GRB 221226B Swift-BAT refined analysis
  54. GRB 221226B: Swift-UVOT Detection
  55. GRB 221226A: AGILE detection
  56. GRB 221226B: Fermi GBM Observation
  57. GRB 221226B: Swift-XRT refined Analysis
  58. GRB 221226B: VLT/X-shooter redshift and host galaxy
  59. GRB 221226B: Enhanced Swift-XRT position
  60. GRB 221226B: Swift detection of a burst
  61. GRB 221226B: Fermi GBM Final Real-time Localization
  62. Swift GRB221226.95: Global MASTER-Net observations report
  63. Fermi GRB 221226A: Global MASTER-Net observations report
  64. GRB 221226A: Fermi GBM Final Real-time Localization
  65. Fermi-LAT gamma-ray observations of IceCube-221224A
  66. IceCube-221224A: BOOTES-4/MET Optical Upper Limit
  67. IceCube-221223A: BOOTES-4/MET Optical Observations
  68. Fermi-LAT gamma-ray observations of IceCube-221223A
  69. Fermi GRB 221223A: Global MASTER-Net observations report
  70. IceCube Alert 221224.04: Global MASTER-Net observations report
  71. GRB 221223A: Fermi GBM Final Real-time Localization
  72. IceCube Alert 221223.32: Global MASTER-Net observations report
  73. IceCube-221223A - IceCube observation of a high-energy neutrino candidate track-like event
  74. GRB 221221A: AGILE detection
  75. Fermi GRB 221221A: Global MASTER-Net observations report
  76. GRB 221221A: Fermi GBM Final Real-time Localization
  77. GRB 221218A: 3.6m DOT optical upper limit
  78. GRB 221216A: Detection by VZLUSAT-2
  79. GRB 221218A: MITSuME Akeno optical upper limits
  80. GRB 221218A: BOOTES-4/MET and OSN optical upper limits
  81. GRB 221218A: KAIT Optical Upper Limit
  82. IceCube-221210A: BOOTES-4/MET and Lijiang 2.4-meter Telescopes Optical Observations
  83. GRB 221215A: Fermi GBM Detection
  84. GRB 221218A: a long GRB detected by INTEGRAL
  85. Integral GRB221218.34: Global MASTER-Net observations report
  86. Fermi-LAT gamma-ray observations of IceCube-221216A
  87. GRB 221216A: Swift/UVOT Upper Limits
  88. GRB 221216A: Fermi GBM observation
  89. GRB 221216A: Swift-XRT refined Analysis
  90. Fermi-LAT gamma-ray observations of IceCube-221210A
  91. IceCube Alert 221216.25: Global MASTER-Net observations report
  92. GRB 221216A: AKO Upper Limit
  93. GRB 221215A: Swift-XRT observations
  94. GRB 221216A: Enhanced Swift-XRT position
  95. Swift GRB 221216A: Global MASTER-Net observations report
  96. GRB 221216A: Zadko observatory - Gingin optical observations
  97. GRB 221216A: Nanshan/NEXT optical upper limits
  98. GRB 221216A: Swift detection of a burst
  99. GRB 221216A: Fermi GBM Final Real-time Localization
  100. IceCube-221216A - IceCube observation of a high-energy neutrino candidate track-like event

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