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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"

27302 results found.

  1. Swift Trigger 1186391 is not a GRB
  2. Swift Trigger 1186390 is not a GRB
  3. Swift Trigger 1186386 is not a GRB
  4. GRB 230812B : GRANDMA/Kilonova-Catcher optical afterglow detection and upper limits
  5. Swift GRB230820.81: Global MASTER-Net observations report
  6. Swift GRB230820.80: Global MASTER-Net observations report
  7. Swift GRB230820.82: Global MASTER-Net observations report
  8. GRB 230818A: Fermi GBM Observation
  9. GRB 230818A: Leavitt Observatory upper limit
  10. GRB 230818A: Swift-XRT refined Analysis
  11. GRB 230818A: Bassano Bresciano Observatory optical observations
  12. GRB 230818A: KGO RC-25 optical observations
  13. GRB 230818A: Swift/UVOT Detection
  14. GRB 230818A: SAO RAS Zeiss-1000 observations
  15. Fermi GRB 230818A: Global MASTER-Net observations report
  16. Fermi trigger No 713974668: Global MASTER-Net observations report
  17. GRB 230818A: GOTO optical afterglow detection
  18. GRB 230818A: Swift detection of a burst
  19. GRB 230818A: Fermi GBM Final Real-time Localization
  20. Swift GRB230818.98: Global MASTER-Net observations report
  21. Swift GRB230818.98: Global MASTER-Net OT detection
  22. GRB 230816A: Swift-BAT refined analysis
  23. GRB 230816A: SVOM/C-GFT optical detection
  24. GRB 230816A: Swift-XRT refined Analysis
  25. GRB 230816A: Osservatorio Astronomico "Nastro Verde" optical observations
  26. GRB 230815A: VLT/HAWK-I near-infrared afterglow detection
  27. Fermi GRB 230817A: Global MASTER-Net observations report
  28. GRB 230817A: BALROG localization (Fermi Trigger 713966581 / GRB 230817502)
  29. GRB 230817A: Fermi GBM Final Real-time Localization
  30. GRB230816A: Possible host and GIT detection of optical counterpart
  31. Swift GRB230816.80: Global MASTER-Net observations report
  32. GRB 230816A: Nanshan/HMT optical afterglow detection
  33. Swift GRB230816.67: Global MASTER-Net observations report
  34. GRB 230816A: Swift detection of a burst
  35. GRB 230815A: Swift-BAT refined analysis
  36. GRB 230815B: GECAM-B and GECAM-C detection of a burst
  37. GRB230815A: Swift/UVOT upper limits
  38. GRB 230812B: GAD Observatory optical observations (upper limit)
  39. GRB 230815A: Swift-XRT refined Analysis
  40. GRB 230812B: iTelescope optical upper limit
  41. GRB230815A: BOOTES-6/DPRT optical upper limit
  42. GRB 230815A: Fermi GBM detection
  43. Swift GRB 230815A: Global MASTER-Net observations report
  44. Fermi GRB 230814A: Global MASTER-Net observations report
  45. GRB 230812B: Iota Scorpii Observatory, La Spezia, Italy
  46. GRB 230815A: Swift detection of a burst
  47. GRB 230812B: Upper limits from a neutrino search with IceCube
  48. GRB 230812B: GRANDMA further observations of ZTF23aaxeacr candidate afterglow
  49. GRB 230814A: BALROG localization (Fermi Trigger 713732101 / GRB 230814788)
  50. GRB 230814A: Fermi GBM Final Real-time Localization
  51. GRB 230812B: GIT optical follow-up
  52. GRB 230812B: Leavitt Observatory optical observations
  53. GRB 230812B : optical observations from Observatoire de Haute-Provence
  54. GRB 230812B: Bassano Bresciano Observatory optical observations
  55. GRB 230812B: Faulkes Telescope North optical afterglow follow-up
  56. GRB 230812B: Osservatorio Astronomico "Nastro Verde" optical observation
  57. GRB 230812B: Spectroscopy from NOT
  58. LIGO/Virgo/KAGRA S230812aj: two counterpart neutrino candidates from IceCube neutrino searches
  59. GRB 230812B: Detected Optical Afterglow Candidate
  60. GRB 230812B: GMG - GRANDMA observations
  61. GRB 230812B: GECAM-C observation of a very bright burst
  62. GRB 230812: Swift/UVOT Detection
  63. GOTO confirmation and possible host galaxy of GRB230812B optical afterglow
  64. GRB 230812B: Zwicky Transient Facility Identifies Optical Afterglow Candidate of a Fermi GRB (Trigger 713559497)
  65. GRB 230812B: Improved Swift/XRT localization
  66. GRB 230812B: Fermi-LAT detection
  67. GRB 230812B: Fermi GBM Observation of a very bright burst
  68. LAT GRB230812.79: Global MASTER-Net observations report
  69. Fermi GRB 230812B: Global MASTER-Net observations report
  70. GRB 230812B: Fermi GBM detection of an extremely bright GRB
  71. GRB 230812B: Fermi GBM Final Real-time Localization
  72. Fermi trigger No 713525317: Global MASTER-Net observations report
  73. GRB 230812A: Fermi GBM Final Real-time Localization
  74. GRB 230808A: Fermi GBM Detection
  75. GRB 230805B: Swift-BAT refined analysis
  76. LIGO/Virgo/KAGRA S230810af: Retraction of GW compact binary merger candidate
  77. GRB 230805B: Iota Scorpii Observatory, La Spezia, Italy upper limit
  78. GRB 230808A: Swift/BAT-GUANO detection of a burst
  79. Fermi trigger No 713136868: Global MASTER-Net observations report
  80. GRB 230808B: Fermi GBM Final Real-time Localization
  81. The Fermi GBM Trigger 713134237 / 230807868 is not associated with LIGO/Virgo/KAGRA S230807f.
  82. Fermi trigger No 713205976: Global MASTER-Net observations report
  83. GRB 230808A: Fermi GBM Final Real-time Localization
  84. GRB 230805B : MITSuME Akeno optical upper limits
  85. LIGO/Virgo/KAGRA S230808i: retraction of a GW unmodeled transient candidate
  86. Fermi GRB 230807A: Global MASTER-Net observations report
  87. Fermi trigger No 713134237: Global MASTER-Net observations report
  88. GRB 230807A: Fermi GBM Final Real-time Localization
  89. LIGO/Virgo/KAGRA S230805x: Upper limits from Swift/BAT-GUANO
  90. GRB 230805B: Fermi GBM observation
  91. GRB 230805B : OHP/T193 optical upper limit
  92. GRB 230806A: Fermi GBM Final Localization
  93. GRB 230805B: Swift/UVOT Upper Limits
  94. Fermi trigger No 712991593: Global MASTER-Net observations report
  95. GRB 230805B: Bassano Bresciano observatory upper limit
  96. Fermi trigger No 712987357: Global MASTER-Net observations report
  97. GRB 230805B: BOOTES-6/DPRT optical upper limit and 1.5m OSN detection
  98. GRB 230805B: NOT optical afterglow confirmation
  99. GRB 230805B: Swift-XRT refined Analysis
  100. Fermi GRB 230805A: Global MASTER-Net observations report

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