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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"

36123 results found.

  1. Fermi Gamma-ray Burst Monitor trigger 220111325/663580106 is not a GRB
  2. GRB 220107A: SAO RAS optical observations
  3. Konus-Wind detection of GRB 220107B
  4. Konus-Wind detection of GRB 220107A
  5. Confirmation of the X-ray afterglow of GRB 220107B
  6. GRB 220107A: further SAO RAS optical observations
  7. GRB 220101A: Additional Liverpool telescope photometry
  8. GRB 220107A: 6m BTA spectroscopic redshift
  9. GRB 220107A: SAO RAS optical observations
  10. GRB 220108A: Swift/BAT-GUANO detection outside the coded FOV
  11. GRB 220101A: SAO RAS optical observations
  12. GRB 220107A: AbAO and Terskol optical observations
  13. GRB 220107B: MITSuME Akeno optical upper limits
  14. GRB 220107B: Nanshan/NEXT optical upper limits and host galaxy candidate
  15. GRB 220107A: Nanshan/NEXT optical observations
  16. GRB 220107A: Swift/UVOT Detection
  17. GRB 220107B: Fermi GBM observations
  18. GRB 220107A: MITSuME Akeno optical observation
  19. GRB 220107B: AstroSat CZTI detection
  20. GRB 220107B: Swift-XRT afterglow detection
  21. GRB 220107A: Swift-XRT afterglow detection
  22. GRB 220107B: Fermi-LAT detection
  23. GRB 220107A: AstroSat CZTI detection
  24. GRB 220107B: Tiled Swift observations
  25. GRB 220107A: Fermi GBM observations
  26. GRB 220107A: Swift ToO observations
  27. Fermi GRB 220107A: Global MASTER-Net observations report
  28. GRB 220107A: Swift/BAT-GUANO arcminute localization
  29. GRB 220101A: Tautenburg observations
  30. GRB 220107A: BALROG localization (Fermi Trigger 663259536 / GRB 220107615)
  31. GRB 220107A: Fermi GBM Final Real-time Localization
  32. GRB 220101A: Continued Mondy optical observations
  33. GRB 220101A: further TNG NIR observations
  34. GRB 220101A: continued 1.3m DFOT Optical Observations
  35. GRB 220104A: Fermi GBM Observation
  36. GRB 220101A: Mondy optical observations
  37. GRB 220101A: 3rd LCO Optical Observation
  38. GRB 220101A: 2.2m CAHA (+CAFOS) first day optical detection
  39. GRB 220101A: iTelescope optical observations
  40. GRB 211227A: Lijiang 2.4m Telescope Optical Observations
  41. GRB 220101A: VLA detection
  42. GRB 220101A: 1.3m DFOT observations
  43. GRB 220101A: LCO Continued Optical Observations
  44. GRB 220104A：GECAM detection
  45. Fermi GRB 220104A: Global MASTER-Net observations report
  46. GRB 220104A: Fermi GBM Final Real-time Localization
  47. GRB 211229B: Fermi GBM observation
  48. Fermi GRB 220103A: Global MASTER-Net observations report
  49. GRB 220103A: Fermi GBM Final Real-time Localization
  50. GRB 211227A: Gemini South Optical Observations
  51. GRB 211229B: Swift/BAT-GUANO detection outside the coded FOV
  52. GRB 220101A: TNG NIR afterglow detection
  53. GRB 220101A: ALMA detection
  54. GRB 220101A: LCO Optical Observations
  55. GRB 220101A: Tautenburg observations
  56. GRB 220101A: Swift-BAT refined analysis
  57. GRB 220101A: GMG observation (2nd epoch)
  58. GRB 211231A: AstroSat CZTI detection
  59. GRB 220101A: OASDG optical observations
  60. GRB 220101A : Eiso equals the maximum isotropic GRB energy
  61. GRB 220101A: GMG observation
  62. GRB 220101A: Asiago spectroscopic and photometric detection
  63. GRB 220101A: Fermi GBM Detection
  64. GRB 220101A: NOT redshift confirmation
  65. GRB 220101A: CAHA 2.2m/CAFOS detection
  66. GRB 220101A: Liverpool telescope imaging of a high-redshift afterglow
  67. GRB 220101A: THO optical observations
  68. GRB 220101A: Swift-XRT refined Analysis
  69. GRB 220101A: AGILE detection
  70. GRB 220101A: Xinglong-2.16m photometry and spectroscopy
  71. GRB 220101: Swift/UVOT Detection
  72. GRB 220101A: Fermi-LAT detection
  73. GRB 220101A: Enhanced Swift-XRT position
  74. GRB 220101A: Correction to GCN 31347
  75. GRB 220101A: Swift detection of a burst with a bright optical counterpart
  76. IPN triangulation of GRB 211219A
  77. GRB 211231A: GECAM detection
  78. GRB 211229B: AGILE detection
  79. GRB 211231A: Fermi GBM Final Real-time Localization
  80. GRB 211229A: Swift-XRT and UVOT observations
  81. GRB 211227A: Deep early CAHA 2.2m/CAFOS observation
  82. GRB 211229A: Fermi GBM observation
  83. GRB 211229B: GECAM detection
  84. GRB 211229C: Swift/BAT-GUANO detection likely outside the coded FOV
  85. Fermi GRB 211229B: Global MASTER-Net observations report
  86. GRB 211229B: Fermi GBM Final Real-time Localization
  87. GRB 211229A: Swift ToO observations
  88. GRB 211229A: Swift/BAT-GUANO arcminute localization
  89. GRB 211227A: CALET Gamma-Ray Burst Monitor detection
  90. GRB 211225B: CALET Gamma-Ray Burst Monitor detection
  91. GRB 211229A: GECAM detection
  92. Fermi GRB 211229A: Global MASTER-Net observations report
  93. GRB 211229A: Fermi GBM Final Real-time Localization
  94. GRB 211227A: Swift/UVOT Upper Limits
  95. GRB 211227A: Swift-XRT refined Analysis
  96. GRB 211227A: Swift-BAT refined analysis
  97. GRB 211227A: A possible short GRB with extended emission at z = 0.228?
  98. GRB 211227A: Liverpool Telescope upper limits
  99. GRB 211227A: Enhanced Swift-XRT position
  100. GRB 211227A: LCO Optical Observations

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