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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"

11659 results found.

  1. GRB 230827B / GRB 230827256: Fermi GBM Observation
  2. GRB 230827A: GRBAlpha detection
  3. GRB 230827A: BALROG localization (Fermi Trigger / GRB 230827762)
  4. Fermi trigger No 714809315: Global MASTER-Net observations report
  5. GRB 230827.256: AKO Optical follow-up of ZTF23abaanxz (AT 2023qxj)
  6. Fermi GRB 230827A: Global MASTER-Net observations report
  7. GRB 230827.256 : GIT optical follow-up of ZTF23abaanxz/AT2023qxj
  8. GRB 230827A: Fermi GBM Final Real-time Localization
  9. AT 2023qxj: ZTF discovery of the likely afterglow of Fermi GRB 230827256
  10. GRB 230826A: GRBAlpha detection
  11. GRB 230826A: Fermi GBM Observation
  12. GRB 230826A: Mondy optical observations
  13. GRB 230826A: Swift detection of a burst
  14. GRB 230826A: Fermi GBM Final Real-time Localization
  15. GRB 230812B: radio detection with the VLA
  16. Fermi Gamma-ray Burst Monitor trigger 714618399/230825046 is not a GRB
  17. Fermi trigger No 714618399: Global MASTER-Net observations report
  18. GRB 230822A: Fermi GBM Observation
  19. GRB 230822A: Swift/BAT-GUANO detection of a burst
  20. IceCube-230823A - IceCube observation of a high-energy neutrino candidate track-like event
  21. GRID detection of GRB 230818A
  22. GRB 230822A: Fermi GBM Final Real-time Localization
  23. GRB 230812B: Assy optical observations, possible SN rise
  24. GRB 230812B: SAO RAS RC-500 and Zeiss-1000 observations
  25. GRB 20230818A: GIT optical upper limit
  26. Konus-Wind detection of GRB 230818A
  27. GRB 230812B : GRANDMA/Kilonova-Catcher optical afterglow detection and upper limits
  28. GRB 230818A: Fermi GBM Observation
  29. GRB 230812B: GIT Confirmation of SN rise
  30. GRB 230818A: Nickel and KAIT telescope optical observations
  31. GRB 230818A: SAO RAS 6-m telescope spectroscopy
  32. GRB 230812B: SAO RAS Zeiss-1000 observations
  33. GRB 230818A: further SAO RAS Zeiss-1000 observations
  34. GRB 230818A: AKO Upper Limit
  35. GRB 230818A: AstroSat CZTI detection
  36. GRB 230818A: Tautenburg observations
  37. GRB 230818A: Leavitt Observatory upper limit
  38. GRB 230818A: Bassano Bresciano Observatory optical observations
  39. GRB 230818A: KGO RC-25 optical observations
  40. GRB 230818A: NOT photometry and spectroscopy
  41. GRB 230818A: SAO RAS Zeiss-1000 observations
  42. Fermi GRB 230818A: Global MASTER-Net observations report
  43. Fermi trigger No 713974668: Global MASTER-Net observations report
  44. GRB 230818A: GOTO optical afterglow detection
  45. GRB 230818A: Fermi GBM Final Real-time Localization
  46. GRB 230812B: SAO RAS observations, possible re-brightening
  47. GRB 230817A: AstroSat CZTI detection
  48. GRB 230812B: SAO RAS optical observations
  49. Fermi GRB 230817A: Global MASTER-Net observations report
  50. GRB 230817A: BALROG localization (Fermi Trigger 713966581 / GRB 230817502)
  51. GRB 230817A: Fermi GBM Final Real-time Localization
  52. GRB 230812B: optical photometry from Konkoly
  53. GRB 230812B: SAO RAS optical observations
  54. GRB 230812B: GAD Observatory optical observations (upper limit)
  55. GRB 230812B: iTelescope optical upper limit
  56. GRB 230812B: continued SAO RAS optical observation
  57. GRB230815A: BOOTES-6/DPRT optical upper limit
  58. GRB 230815A: Fermi GBM detection
  59. Fermi GRB 230814A: Global MASTER-Net observations report
  60. GRB 230812B: continued AbAO optical afterglow observations
  61. GRB 230812B: Optical observaions from Rozhen Observatory
  62. GRB 230812B: Upper limits from a neutrino search with IceCube
  63. GRB 230812B: GRANDMA further observations of ZTF23aaxeacr candidate afterglow
  64. GRB 230814A: BALROG localization (Fermi Trigger 713732101 / GRB 230814788)
  65. GRB 230812B: CrAO ZTSh optical observations
  66. GRB 230814A: Fermi GBM Final Real-time Localization
  67. GRB 230812B: Koshka Zeiss-1000 optical observations
  68. GRB 230812B: GIT optical follow-up
  69. GRB 230812B: Leavitt Observatory optical observations
  70. GRB 230812B : optical observations from Observatoire de Haute-Provence
  71. GRB 230812B: Bassano Bresciano Observatory optical observations
  72. GRB 230812B: Faulkes Telescope North optical afterglow follow-up
  73. GRB 230812B: AbAO optical observations
  74. GRB 230812B: Redshift from OSIRIS+/GTC
  75. Konus-Wind detection of GRB 230812B
  76. GRB230812B: AGILE/MCAL detection
  77. GRB 230812B: GECAM-C observation of a very bright burst
  78. GRB 230812B: Swift-XRT afterglow detection
  79. GRB 230812: Swift/UVOT Detection
  80. GRB 230812B: Zwicky Transient Facility Identifies Optical Afterglow Candidate of a Fermi GRB (Trigger 713559497)
  81. Fermi GRB 230812B: MASTER optical counterpart
  82. GRB 230812B: KAIT Optical Afterglow Candidate
  83. GRB 230812B: Improved Swift/XRT localization
  84. GRB 230812B: Fermi-LAT detection
  85. GRB 230812B: Fermi GBM Observation of a very bright burst
  86. Fermi GRB 230812B: Global MASTER-Net observations report
  87. GRB 230812B: Tiled Swift observations
  88. GRB 230812B: Fermi GBM detection of an extremely bright GRB
  89. GRB 230812B: Fermi GBM Final Real-time Localization
  90. Fermi trigger No 713525317: Global MASTER-Net observations report
  91. GRB 230812A: Fermi GBM Final Real-time Localization
  92. GRB 230808A: Fermi GBM Detection
  93. GRB 230805B: AstroSat CZTI detection
  94. GRB 230808A: Swift/BAT-GUANO detection of a burst
  95. Fermi trigger No 713136868: Global MASTER-Net observations report
  96. GRB 230808B: Fermi GBM Final Real-time Localization
  97. The Fermi GBM Trigger 713134237 / 230807868 is not associated with LIGO/Virgo/KAGRA S230807f.
  98. Fermi trigger No 713205976: Global MASTER-Net observations report
  99. GRB 230808A: Fermi GBM Final Real-time Localization
  100. Fermi GRB 230807A: Global MASTER-Net observations report

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