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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"

21526 results found.

  1. MAXI/GSC detection of Swift J1727.8-1613 (GRB 230824A)
  2. GRB 230824A: AKO Optical Afterglow Candidate
  3. Trigger 1186982: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)
  4. GRB 230824A is likely a Galactic Transient: Swift J1727.8-1613
  5. GRB 230824A: Swift detection of a burst
  6. Swift GRB230824.58: Global MASTER-Net observations report
  7. Swift GRB230824.10: Global MASTER-Net observations report
  8. Swift Trigger 1186908 is not a GRB
  9. GRB 230822A: Fermi GBM Observation
  10. LIGO/Virgo/KAGRA S230822bm: Upper limits from Swift/BAT-GUANO
  11. GRB 230822A: Swift/BAT-GUANO detection of a burst
  12. GRID detection of GRB 230818A
  13. GRB 230815A: ATCA detection of radio counterpart
  14. Swift GRB230821.64: Global MASTER-Net observations report
  15. GRB 230818A: Swift-BAT refined analysis
  16. Swift Trigger 1186391 is not a GRB
  17. Swift Trigger 1186390 is not a GRB
  18. Konus-Wind detection of GRB 230818A
  19. Swift Trigger 1186386 is not a GRB
  20. Swift triggers 1186294-1186304 are not astrophysical transients
  21. Swift GRB230820.81: Global MASTER-Net observations report
  22. Swift GRB230820.80: Global MASTER-Net observations report
  23. Swift GRB230820.82: Global MASTER-Net observations report
  24. Swift Triggers 1186280 and 1186291 are not GRBs
  25. GRB 230818A: Fermi GBM Observation
  26. GRB 230818A: SAO RAS 6-m telescope spectroscopy
  27. GRB 230818A: AKO Upper Limit
  28. GRB 230818A: AstroSat CZTI detection
  29. GRB 230818A: Leavitt Observatory upper limit
  30. GRB 230818A: Swift-XRT refined Analysis
  31. GRB 230818A: Bassano Bresciano Observatory optical observations
  32. GRB 230818A: KGO RC-25 optical observations
  33. GRB 230818A: Swift/UVOT Detection
  34. GRB 230818A: NOT photometry and spectroscopy
  35. GRB 230818A: Enhanced Swift-XRT position
  36. GRB 230818A: Swift detection of a burst
  37. Swift GRB230818.98: Global MASTER-Net observations report
  38. Swift GRB230818.98: Global MASTER-Net OT detection
  39. GRB 230816A: Swift-BAT refined analysis
  40. GRB 230816A: SVOM/C-GFT optical detection
  41. GRB 230816A: Swift-XRT refined Analysis
  42. GRB 230816A: Osservatorio Astronomico "Nastro Verde" optical observations
  43. GRB 230815A: VLT/HAWK-I near-infrared afterglow detection
  44. GRB 230816A: Enhanced Swift-XRT position
  45. GRB230816A: Possible host and GIT detection of optical counterpart
  46. Swift GRB230816.80: Global MASTER-Net observations report
  47. IPN triangulation of GRB 230815B
  48. GRB 230816A: Nanshan/HMT optical afterglow detection
  49. GRB 230815A: SOAR/Goodman follow-up imaging
  50. Swift GRB230816.67: Global MASTER-Net observations report
  51. GRB 230816A: Swift detection of a burst
  52. GRB 230815A: Swift-BAT refined analysis
  53. GRB230815A: Swift/UVOT upper limits
  54. GRB 230812B: GAD Observatory optical observations (upper limit)
  55. GRB 230815A: Swift-XRT refined Analysis
  56. GRB 230812B: iTelescope optical upper limit
  57. GRB230815A: BOOTES-6/DPRT optical upper limit
  58. GRB 230815A: Fermi GBM detection
  59. Swift GRB 230815A: Global MASTER-Net observations report
  60. GRB 230815A: Enhanced Swift-XRT position
  61. GRB 230815A: Swift detection of a burst
  62. GRB 230812B: Upper limits from a neutrino search with IceCube
  63. GRB 230812B: GIT optical follow-up
  64. GRB 230812B: Faulkes Telescope North optical afterglow follow-up
  65. GRB 230812B: Osservatorio Astronomico "Nastro Verde" optical observation
  66. GRB 230812B: OASDG optical observations
  67. GRB 230812B: Detected Optical Afterglow Candidate
  68. GRB230812B: AGILE/MCAL detection
  69. GRB 230812B: Swift-XRT afterglow detection
  70. GRB 230812: Swift/UVOT Detection
  71. GOTO confirmation and possible host galaxy of GRB230812B optical afterglow
  72. GRB 230812B: Zwicky Transient Facility Identifies Optical Afterglow Candidate of a Fermi GRB (Trigger 713559497)
  73. Fermi GRB 230812B: MASTER optical counterpart
  74. GRB 230812B: KAIT Optical Afterglow Candidate
  75. GRB 230812B: Improved Swift/XRT localization
  76. GRB 230812B: Preliminary Swift/XRT localization
  77. GRB 230812B: Tiled Swift observations
  78. GRB 230808A: Fermi GBM Detection
  79. GRB 230805B: Swift-BAT refined analysis
  80. GRB 230805B: Iota Scorpii Observatory, La Spezia, Italy upper limit
  81. GRB 230805B: AstroSat CZTI detection
  82. GRB 230808A: Swift/BAT-GUANO detection of a burst
  83. GRB 230805B : MITSuME Akeno optical upper limits
  84. LIGO/Virgo/KAGRA S230805x: Upper limits from Swift/BAT-GUANO
  85. GRB 230805B: Fermi GBM observation
  86. GRB 230805B: Enhanced Swift-XRT position
  87. GRB 230805B: Swift/UVOT Upper Limits
  88. GRB 230805B: Bassano Bresciano observatory upper limit
  89. GRB 230805B: BOOTES-6/DPRT optical upper limit and 1.5m OSN detection
  90. GRB 230805B: Swift-XRT refined Analysis
  91. GRB 230805B: SAO RAS optical observations
  92. Swift GRB 230805B: Global MASTER-Net observations report
  93. GRB 230805B: Swift detection of a burst
  94. GRB 230802A: Fermi GBM observation
  95. GRB 230802A: Swift-BAT refined analysis
  96. GRB 230802A: Swift/UVOT Upper Limits
  97. Swift GRB 230802A: Global MASTER-Net observations report
  98. GRB 230802A: BOOTES-5/JGT optical upper limit
  99. GRB 230802A: Swift-XRT refined Analysis
  100. GRB 230802A: Enhanced Swift-XRT position

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