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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"

36354 results found.

  1. Trigger 1187142: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)
  2. MAXI/GSC detection of Swift J1727.8-1613 (GRB 230824A)
  3. GRB 230824A: AKO Optical Afterglow Candidate
  4. Trigger 1186982: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)
  5. IBAS trigger 10375 is not a GRB
  6. GRB 230824A is likely a Galactic Transient: Swift J1727.8-1613
  7. GRB 230824B: AstroSat CZTI detection
  8. GRB 230824A: Swift detection of a burst
  9. Swift Trigger 1186908 is not a GRB
  10. GRB 230822A: Fermi GBM Observation
  11. LIGO/Virgo/KAGRA S230822bm: Upper limits from Swift/BAT-GUANO
  12. GRB 230822A: Swift/BAT-GUANO detection of a burst
  13. IceCube-230823A: Event likely due to background
  14. GRB 230812B: AstroSat LAXPC detection
  15. GRB 230818B: VZLUSAT-2 detection
  16. GRB 230818B: AstroSat CZTI detection
  17. GRID detection of GRB 230818A
  18. GRB 230822A: Fermi GBM Final Real-time Localization
  19. GRB 230812B: Assy optical observations, possible SN rise
  20. GRB 230815A: ATCA detection of radio counterpart
  21. GRB 230812B: SAO RAS RC-500 and Zeiss-1000 observations
  22. GRB 230818A: Swift-BAT refined analysis
  23. GRB 20230818A: GIT optical upper limit
  24. Swift Trigger 1186391 is not a GRB
  25. Swift Trigger 1186390 is not a GRB
  26. Konus-Wind detection of GRB 230818A
  27. Swift Trigger 1186386 is not a GRB
  28. GRB 230812B : GRANDMA/Kilonova-Catcher optical afterglow detection and upper limits
  29. GRB 230820A: AstroSat CZTI detection
  30. GRB 230818A: Fermi GBM Observation
  31. GRB 230812B: GIT Confirmation of SN rise
  32. GRB 230818A: Nickel and KAIT telescope optical observations
  33. GRB 230818A: SAO RAS 6-m telescope spectroscopy
  34. GRB 230812B: SAO RAS Zeiss-1000 observations
  35. GRB 230818A: further SAO RAS Zeiss-1000 observations
  36. GRB 230818A: AKO Upper Limit
  37. GRB 230818A: AstroSat CZTI detection
  38. GRB 230818A: Tautenburg observations
  39. GRB 230818A: Leavitt Observatory upper limit
  40. GRB 230818A: Swift-XRT refined Analysis
  41. GRB 230818A: Bassano Bresciano Observatory optical observations
  42. GRB 230818A: KGO RC-25 optical observations
  43. GRB 230818A: Swift/UVOT Detection
  44. GRB 230818A: NOT photometry and spectroscopy
  45. GRB 230818A: Enhanced Swift-XRT position
  46. GRB 230818A: SAO RAS Zeiss-1000 observations
  47. Fermi GRB 230818A: Global MASTER-Net observations report
  48. GRB 230818A: GOTO optical afterglow detection
  49. GRB 230818A: Swift detection of a burst
  50. GRB 230818A: Fermi GBM Final Real-time Localization
  51. GRB 230812B: SAO RAS observations, possible re-brightening
  52. GRB 230816A: Swift-BAT refined analysis
  53. GRB 230816A: SVOM/C-GFT optical detection
  54. GRB 230817A: AstroSat CZTI detection
  55. GRB 230812B: SAO RAS optical observations
  56. GRB 230816A: Swift-XRT refined Analysis
  57. GRB 230816A: Osservatorio Astronomico "Nastro Verde" optical observations
  58. GRB 230812B: NOEMA detection
  59. GRB 230815A: VLT/HAWK-I near-infrared afterglow detection
  60. Fermi GRB 230817A: Global MASTER-Net observations report
  61. GRB 230817A: BALROG localization (Fermi Trigger 713966581 / GRB 230817502)
  62. GRB 230817A: Fermi GBM Final Real-time Localization
  63. GRB 230812B: optical photometry from Konkoly
  64. GRB 230816A: Enhanced Swift-XRT position
  65. GRB 230812B: SAO RAS optical observations
  66. GRB230816A: Possible host and GIT detection of optical counterpart
  67. GRB 230816A: Tautenburg observations
  68. GRB 230816A: AKO Optical Observations
  69. GRB 230816A: TShAO and Assy optical observations
  70. GRB 230816A: SAO RAS optical observations
  71. IPN triangulation of GRB 230815B
  72. GRB 230816A: Nanshan/HMT optical afterglow detection
  73. GRB 230815A: SOAR/Goodman follow-up imaging
  74. GRB 230816A: Swift detection of a burst
  75. GRB 230815A: Swift-BAT refined analysis
  76. GRB 230815B: GECAM-B and GECAM-C detection of a burst
  77. GRB 230815B: AstroSat CZTI detection
  78. GRB230815A: Swift/UVOT upper limits
  79. GRB 230812B: GAD Observatory optical observations (upper limit)
  80. GRB 230815A: Swift-XRT refined Analysis
  81. GRB 230812B: iTelescope optical upper limit
  82. GRB 230812B: continued SAO RAS optical observation
  83. GRB230815A: BOOTES-6/DPRT optical upper limit
  84. GRB 230815A: Fermi GBM detection
  85. Swift GRB 230815A: Global MASTER-Net observations report
  86. Fermi GRB 230814A: Global MASTER-Net observations report
  87. GRB 230815A: Enhanced Swift-XRT position
  88. GRB 230812B: Iota Scorpii Observatory, La Spezia, Italy
  89. GRB 230812B: Tautenburg observations
  90. GRB 230815A: Swift detection of a burst
  91. GRB 230812B: AMI-LA radio detection of afterglow candidate
  92. GRB 230812B: continued AbAO optical afterglow observations
  93. GRB 230812B: Optical observaions from Rozhen Observatory
  94. GRB 230812B: Further Bassano Bresciano Observatory optical observations
  95. GRB 230812B: further SAO RAS optical observations
  96. GRB 230812B: Upper limits from a neutrino search with IceCube
  97. GRB 230812B: GRANDMA further observations of ZTF23aaxeacr candidate afterglow
  98. GRB 230814A: BALROG localization (Fermi Trigger 713732101 / GRB 230814788)
  99. GRB 230812B: CrAO ZTSh optical observations
  100. GRB 230814A: Fermi GBM Final Real-time Localization

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