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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"

28252 results found.

  1. GRB 230826A: Fermi GBM Final Real-time Localization
  2. GRB 230818B: CALET Gamma-Ray Burst Monitor detection
  3. Trigger 1187225: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)
  4. Trigger 1187207: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)
  5. Trigger 1187203: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)
  6. GRB 230812B: radio detection with the VLA
  7. NICER detection of Swift J1727.8-1613 (GRB 230824A)
  8. Trigger 1187142: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)
  9. MAXI/GSC detection of Swift J1727.8-1613 (GRB 230824A)
  10. GRB 230824A: AKO Optical Afterglow Candidate
  11. Trigger 1186982: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)
  12. GRB 230824B: AstroSat CZTI detection
  13. GRB 230824A: Swift detection of a burst
  14. GRB 230822A: Swift/BAT-GUANO detection of a burst
  15. IceCube-230823A - IceCube observation of a high-energy neutrino candidate track-like event
  16. GRB 230812B: AstroSat LAXPC detection
  17. GRB 230818B: VZLUSAT-2 detection
  18. GRB 230818B: AstroSat CZTI detection
  19. GRID detection of GRB 230818A
  20. GRB 230822A: Fermi GBM Final Real-time Localization
  21. GRB 230815A: ATCA detection of radio counterpart
  22. GRB 20230818A: GIT optical upper limit
  23. Konus-Wind detection of GRB 230818A
  24. GRB 230812B : GRANDMA/Kilonova-Catcher optical afterglow detection and upper limits
  25. GRB 230820A: AstroSat CZTI detection
  26. GRB 230812B: GIT Confirmation of SN rise
  27. GRB 230818A: Nickel and KAIT telescope optical observations
  28. GRB 230818A: SAO RAS 6-m telescope spectroscopy
  29. GRB 230818A: AKO Upper Limit
  30. GRB 230818A: AstroSat CZTI detection
  31. GRB 230818A: Swift-XRT refined Analysis
  32. GRB 230818A: Bassano Bresciano Observatory optical observations
  33. GRB 230818A: KGO RC-25 optical observations
  34. GRB 230818A: Swift/UVOT Detection
  35. GRB 230818A: Enhanced Swift-XRT position
  36. GRB 230818A: GOTO optical afterglow detection
  37. GRB 230818A: Swift detection of a burst
  38. GRB 230818A: Fermi GBM Final Real-time Localization
  39. Swift GRB230818.98: Global MASTER-Net OT detection
  40. GRB 230816A: SVOM/C-GFT optical detection
  41. GRB 230817A: AstroSat CZTI detection
  42. GRB 230816A: Swift-XRT refined Analysis
  43. GRB 230816A: Osservatorio Astronomico "Nastro Verde" optical observations
  44. GRB 230812B: NOEMA detection
  45. GRB 230815A: VLT/HAWK-I near-infrared afterglow detection
  46. GRB 230817A: Fermi GBM Final Real-time Localization
  47. GRB 230812B: optical photometry from Konkoly
  48. GRB 230816A: Enhanced Swift-XRT position
  49. GRB230816A: Possible host and GIT detection of optical counterpart
  50. GRB 230816A: AKO Optical Observations
  51. GRB 230816A: TShAO and Assy optical observations
  52. IPN triangulation of GRB 230815B
  53. GRB 230816A: Nanshan/HMT optical afterglow detection
  54. GRB 230815A: SOAR/Goodman follow-up imaging
  55. GRB 230816A: Swift detection of a burst
  56. GRB 230815B: GECAM-B and GECAM-C detection of a burst
  57. GRB 230815B: AstroSat CZTI detection
  58. GRB230815A: Swift/UVOT upper limits
  59. GRB 230812B: GAD Observatory optical observations (upper limit)
  60. GRB 230815A: Swift-XRT refined Analysis
  61. GRB 230812B: iTelescope optical upper limit
  62. GRB230815A: BOOTES-6/DPRT optical upper limit
  63. GRB 230815A: Fermi GBM detection
  64. GRB 230815A: Enhanced Swift-XRT position
  65. GRB 230812B: Iota Scorpii Observatory, La Spezia, Italy
  66. GRB 230815A: Swift detection of a burst
  67. GRB 230812B: AMI-LA radio detection of afterglow candidate
  68. GRB 230812B: continued AbAO optical afterglow observations
  69. GRB 230812B: Optical observaions from Rozhen Observatory
  70. GRB 230812B: Further Bassano Bresciano Observatory optical observations
  71. GRB 230812B: Upper limits from a neutrino search with IceCube
  72. GRB 230812B: GRANDMA further observations of ZTF23aaxeacr candidate afterglow
  73. GRB 230812B: CrAO ZTSh optical observations
  74. GRB 230814A: Fermi GBM Final Real-time Localization
  75. GRB 230812B: Koshka Zeiss-1000 optical observations
  76. GRB 230812B: GIT optical follow-up
  77. GRB 230812B: Leavitt Observatory optical observations
  78. GRB 230812B: Bassano Bresciano Observatory optical observations
  79. GRB 230812B: Faulkes Telescope North optical afterglow follow-up
  80. GRB 230812B: Osservatorio Astronomico "Nastro Verde" optical observation
  81. GRB 230812B: OASDG optical observations
  82. GRB 230812B: AbAO optical observations
  83. GRB 230812B: Spectroscopy from NOT
  84. GRB 230812B: Redshift from OSIRIS+/GTC
  85. GRB 230812B: Detected Optical Afterglow Candidate
  86. GRB 230812B: GMG - GRANDMA observations
  87. Konus-Wind detection of GRB 230812B
  88. GRB230812B: AGILE/MCAL detection
  89. GRB 230812B: Swift-XRT afterglow detection
  90. GRB 230812: Swift/UVOT Detection
  91. GOTO confirmation and possible host galaxy of GRB230812B optical afterglow
  92. GRB 230812B: Zwicky Transient Facility Identifies Optical Afterglow Candidate of a Fermi GRB (Trigger 713559497)
  93. Fermi GRB 230812B: MASTER optical counterpart
  94. GRB 230812B: KAIT Optical Afterglow Candidate
  95. GRB 230812B: Improved Swift/XRT localization
  96. GRB 230812B: Preliminary Swift/XRT localization
  97. GRB 230812B: Fermi-LAT detection
  98. GRB 230812B: Tiled Swift observations
  99. GRB 230812B: Fermi GBM detection of an extremely bright GRB
  100. GRB 230812B: Fermi GBM Final Real-time Localization

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