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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"

39367 results found.

  1. Swift J1727.8-1613 (GRB 230824A): GAD Observatory La Spezia - optical observations
  2. GRB 230826A: Swift detection of a burst
  3. GRB 230826A: Fermi GBM Final Real-time Localization
  4. Swift GRB230826.81: Global MASTER-Net observations report
  5. Swift J1727.8-1613 (GRB 230824A): Bassano Bresciano Observatory optical observations
  6. GRB 230824A: AKO Photometric Follow-up Observations
  7. GRB 230818B: CALET Gamma-Ray Burst Monitor detection
  8. LIGO/Virgo/KAGRA S230825k: Upper limits from Swift/BAT-GUANO
  9. Swift GRB230825.85: Global MASTER-Net observations report
  10. Trigger 1187225: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)
  11. Swift J1727.8-1613 (GRB 230824A): Skynet Optical Observations
  12. Trigger 1187207: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)
  13. Trigger 1187203: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)
  14. Swift GRB230825.75: Global MASTER-Net observations report
  15. GRB 230812B: radio detection with the VLA
  16. Fermi Gamma-ray Burst Monitor trigger 714618399/230825046 is not a GRB
  17. NICER detection of Swift J1727.8-1613 (GRB 230824A)
  18. Trigger 1187142: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)
  19. Fermi trigger No 714618399: Global MASTER-Net observations report
  20. MAXI/GSC detection of Swift J1727.8-1613 (GRB 230824A)
  21. GRB 230824A: AKO Optical Afterglow Candidate
  22. Trigger 1186982: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)
  23. IBAS trigger 10375 is not a GRB
  24. GRB 230824A is likely a Galactic Transient: Swift J1727.8-1613
  25. Integral GRB230824.72: Global MASTER-Net observations report
  26. GRB 230824B: AstroSat CZTI detection
  27. GRB 230824A: Swift detection of a burst
  28. Swift GRB230824.58: Global MASTER-Net observations report
  29. Swift GRB230824.10: Global MASTER-Net observations report
  30. Swift Trigger 1186908 is not a GRB
  31. GRB 230822A: Fermi GBM Observation
  32. LIGO/Virgo/KAGRA S230822bm: Upper limits from Swift/BAT-GUANO
  33. GRB 230822A: Swift/BAT-GUANO detection of a burst
  34. GRB 230812B: AstroSat LAXPC detection
  35. GRB 230818B: VZLUSAT-2 detection
  36. GRB 230818B: AstroSat CZTI detection
  37. GRID detection of GRB 230818A
  38. GRB 230822A: Fermi GBM Final Real-time Localization
  39. GRB 230812B: Assy optical observations, possible SN rise
  40. GRB 230815A: ATCA detection of radio counterpart
  41. Swift GRB230821.64: Global MASTER-Net observations report
  42. GRB 230812B: SAO RAS RC-500 and Zeiss-1000 observations
  43. GRB 230818A: Swift-BAT refined analysis
  44. GRB 20230818A: GIT optical upper limit
  45. Swift Trigger 1186391 is not a GRB
  46. Swift Trigger 1186390 is not a GRB
  47. Konus-Wind detection of GRB 230818A
  48. Swift Trigger 1186386 is not a GRB
  49. GRB 230812B : GRANDMA/Kilonova-Catcher optical afterglow detection and upper limits
  50. Swift GRB230820.81: Global MASTER-Net observations report
  51. Swift GRB230820.80: Global MASTER-Net observations report
  52. GRB 230820A: AstroSat CZTI detection
  53. Swift GRB230820.82: Global MASTER-Net observations report
  54. GRB 230818A: Fermi GBM Observation
  55. GRB 230812B: GIT Confirmation of SN rise
  56. GRB 230818A: Nickel and KAIT telescope optical observations
  57. GRB 230818A: SAO RAS 6-m telescope spectroscopy
  58. GRB 230812B: SAO RAS Zeiss-1000 observations
  59. GRB 230818A: further SAO RAS Zeiss-1000 observations
  60. GRB 230818A: AKO Upper Limit
  61. GRB 230818A: AstroSat CZTI detection
  62. GRB 230818A: Tautenburg observations
  63. GRB 230818A: Leavitt Observatory upper limit
  64. GRB 230818A: Swift-XRT refined Analysis
  65. GRB 230818A: Bassano Bresciano Observatory optical observations
  66. GRB 230818A: KGO RC-25 optical observations
  67. GRB 230818A: Swift/UVOT Detection
  68. GRB 230818A: NOT photometry and spectroscopy
  69. GRB 230818A: Enhanced Swift-XRT position
  70. GRB 230818A: SAO RAS Zeiss-1000 observations
  71. Fermi GRB 230818A: Global MASTER-Net observations report
  72. Fermi trigger No 713974668: Global MASTER-Net observations report
  73. GRB 230818A: GOTO optical afterglow detection
  74. GRB 230818A: Swift detection of a burst
  75. GRB 230818A: Fermi GBM Final Real-time Localization
  76. Swift GRB230818.98: Global MASTER-Net observations report
  77. Swift GRB230818.98: Global MASTER-Net OT detection
  78. GRB 230812B: SAO RAS observations, possible re-brightening
  79. GRB 230816A: Swift-BAT refined analysis
  80. GRB 230816A: SVOM/C-GFT optical detection
  81. GRB 230817A: AstroSat CZTI detection
  82. GRB 230812B: SAO RAS optical observations
  83. GRB 230816A: Swift-XRT refined Analysis
  84. GRB 230816A: Osservatorio Astronomico "Nastro Verde" optical observations
  85. GRB 230812B: NOEMA detection
  86. GRB 230815A: VLT/HAWK-I near-infrared afterglow detection
  87. Fermi GRB 230817A: Global MASTER-Net observations report
  88. GRB 230817A: BALROG localization (Fermi Trigger 713966581 / GRB 230817502)
  89. GRB 230817A: Fermi GBM Final Real-time Localization
  90. GRB 230812B: optical photometry from Konkoly
  91. GRB 230816A: Enhanced Swift-XRT position
  92. GRB 230812B: SAO RAS optical observations
  93. GRB230816A: Possible host and GIT detection of optical counterpart
  94. GRB 230816A: Tautenburg observations
  95. GRB 230816A: AKO Optical Observations
  96. GRB 230816A: TShAO and Assy optical observations
  97. GRB 230816A: SAO RAS optical observations
  98. Swift GRB230816.80: Global MASTER-Net observations report
  99. IPN triangulation of GRB 230815B
  100. GRB 230816A: Nanshan/HMT optical afterglow detection

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