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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"

36109 results found.

  1. GRB 220107A: Nanshan/NEXT optical observations
  2. GRB 220107A: Swift/UVOT Detection
  3. GRB 220107B: Fermi GBM observations
  4. GRB 220107A: MITSuME Akeno optical observation
  5. GRB 220107B: AstroSat CZTI detection
  6. GRB 220107B: Swift-XRT afterglow detection
  7. GRB 220107A: Swift-XRT afterglow detection
  8. GRB 220107B: Fermi-LAT detection
  9. GRB 220107A: AstroSat CZTI detection
  10. GRB 220107B: Tiled Swift observations
  11. GRB 220107A: Fermi GBM observations
  12. GRB 220107A: Swift ToO observations
  13. Fermi GRB 220107A: Global MASTER-Net observations report
  14. GRB 220107A: Swift/BAT-GUANO arcminute localization
  15. GRB 220101A: Tautenburg observations
  16. GRB 220107A: BALROG localization (Fermi Trigger 663259536 / GRB 220107615)
  17. GRB 220107A: Fermi GBM Final Real-time Localization
  18. GRB 220101A: Continued Mondy optical observations
  19. GRB 220101A: further TNG NIR observations
  20. GRB 220101A: continued 1.3m DFOT Optical Observations
  21. GRB 220104A: Fermi GBM Observation
  22. GRB 220101A: Mondy optical observations
  23. GRB 220101A: 3rd LCO Optical Observation
  24. GRB 220101A: 2.2m CAHA (+CAFOS) first day optical detection
  25. GRB 220101A: iTelescope optical observations
  26. GRB 211227A: Lijiang 2.4m Telescope Optical Observations
  27. GRB 220101A: VLA detection
  28. GRB 220101A: 1.3m DFOT observations
  29. GRB 220101A: LCO Continued Optical Observations
  30. GRB 220104A：GECAM detection
  31. Fermi GRB 220104A: Global MASTER-Net observations report
  32. GRB 220104A: Fermi GBM Final Real-time Localization
  33. GRB 211229B: Fermi GBM observation
  34. Fermi GRB 220103A: Global MASTER-Net observations report
  35. GRB 220103A: Fermi GBM Final Real-time Localization
  36. GRB 211227A: Gemini South Optical Observations
  37. GRB 211229B: Swift/BAT-GUANO detection outside the coded FOV
  38. GRB 220101A: TNG NIR afterglow detection
  39. GRB 220101A: ALMA detection
  40. GRB 220101A: LCO Optical Observations
  41. GRB 220101A: Tautenburg observations
  42. GRB 220101A: Swift-BAT refined analysis
  43. GRB 220101A: GMG observation (2nd epoch)
  44. GRB 211231A: AstroSat CZTI detection
  45. GRB 220101A: OASDG optical observations
  46. GRB 220101A : Eiso equals the maximum isotropic GRB energy
  47. GRB 220101A: GMG observation
  48. GRB 220101A: Asiago spectroscopic and photometric detection
  49. GRB 220101A: Fermi GBM Detection
  50. GRB 220101A: NOT redshift confirmation
  51. GRB 220101A: CAHA 2.2m/CAFOS detection
  52. GRB 220101A: Liverpool telescope imaging of a high-redshift afterglow
  53. GRB 220101A: THO optical observations
  54. GRB 220101A: Swift-XRT refined Analysis
  55. GRB 220101A: AGILE detection
  56. GRB 220101A: Xinglong-2.16m photometry and spectroscopy
  57. GRB 220101: Swift/UVOT Detection
  58. GRB 220101A: Fermi-LAT detection
  59. GRB 220101A: Enhanced Swift-XRT position
  60. GRB 220101A: Correction to GCN 31347
  61. GRB 220101A: Swift detection of a burst with a bright optical counterpart
  62. IPN triangulation of GRB 211219A
  63. GRB 211231A: GECAM detection
  64. GRB 211229B: AGILE detection
  65. GRB 211231A: Fermi GBM Final Real-time Localization
  66. GRB 211229A: Swift-XRT and UVOT observations
  67. GRB 211227A: Deep early CAHA 2.2m/CAFOS observation
  68. GRB 211229A: Fermi GBM observation
  69. GRB 211229B: GECAM detection
  70. GRB 211229C: Swift/BAT-GUANO detection likely outside the coded FOV
  71. Fermi GRB 211229B: Global MASTER-Net observations report
  72. GRB 211229B: Fermi GBM Final Real-time Localization
  73. GRB 211229A: Swift ToO observations
  74. GRB 211229A: Swift/BAT-GUANO arcminute localization
  75. GRB 211227A: CALET Gamma-Ray Burst Monitor detection
  76. GRB 211225B: CALET Gamma-Ray Burst Monitor detection
  77. GRB 211229A: GECAM detection
  78. Fermi GRB 211229A: Global MASTER-Net observations report
  79. GRB 211229A: Fermi GBM Final Real-time Localization
  80. GRB 211227A: Swift/UVOT Upper Limits
  81. GRB 211227A: Swift-XRT refined Analysis
  82. GRB 211227A: Swift-BAT refined analysis
  83. GRB 211227A: A possible short GRB with extended emission at z = 0.228?
  84. GRB 211227A: Liverpool Telescope upper limits
  85. GRB 211227A: Enhanced Swift-XRT position
  86. GRB 211227A: LCO Optical Observations
  87. GRB 211227A: Nanshan/NEXT optical observations and host galaxy candidate
  88. GRB 211227A: MAXI/GSC detection
  89. GRB 211227A: BOOTES-2/TELMA optical upper limit
  90. GRB 211221A: Swift/UVOT Upper Limits
  91. GRB 211227A: Swift detection of a burst
  92. GRB 211226A: Swift/BAT-GUANO detection outside the coded FOV
  93. GRB 211225B: Swift-BAT refined analysis
  94. GRB 211225A: MITSuME Akeno optical upper limits
  95. GRB 211226A: AGILE/MCAL detection of a burst
  96. Swift GRB 211225B: Global MASTER-Net observations report
  97. Fermi GRB 211225C: Global MASTER-Net observations report
  98. GRB 211225C: Fermi GBM Final Real-time Localization
  99. GRB 211225B: Swift detection of a burst
  100. GRB 211225A/MAXI J0827-071: MAXI/GSC detection

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