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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"

14950 results found.

  1. GRB 230308A: Fermi GBM detection
  2. GRB 230307A: ASO-S/HXI detection
  3. GRB 230307A: AstroSat LAXPC detection
  4. GRB 230308A: AGILE/MCAL detection
  5. GRB 230307A: optical upper limit
  6. GRB 230217A: ATCA rapid-response radio detection
  7. GRB 230307A: Swift/BAT upper limits on the early afterglow
  8. Konus-Wind detection of GRB 230307A
  9. GRB 230307A: VZLUSAT-2 detection
  10. GRB 230304B: CALET Gamma-Ray Burst Monitor detection
  11. GRB 230308A: Fermi GBM Final Real-time Localization
  12. GRB 230307A: Detection by GRBAlpha
  13. GRB 230305A: Detection by GRBAlpha
  14. GRB 230307A: AstroSat CZTI detection
  15. GRB 230307A: possibly the second highest GRB energy fluence ever identified
  16. IPN triangulation of GRB 230307A (long/very bright)
  17. GRB 230307A: AGILE/MCAL detection
  18. GRB 230307A: Fermi GBM detection of a very bright GRB
  19. GRB 230307A: GECAM detection of an extremely bright burst
  20. GRB 230307A: Fermi GBM Final Real-time Localization
  21. IceCube-230306A - IceCube observation of a high-energy neutrino candidate
  22. GRB 230304C: AstroSat CZTI detection
  23. GRB 230304B: AstroSat CZTI detection
  24. GRB 230304A: AstroSat CZTI detection
  25. GRB 230304B: Detection by GRBAlpha
  26. GRB 230304C: Fermi GBM Final Real-time Localization
  27. GRB 230304B: Fermi GBM Final Real-time Localization
  28. GRB 230304A: Fermi GBM Final Real-time Localization
  29. GRB 230301B: Fermi GBM Final Real-time Localization
  30. GRB 230228A: OSN optical upper limit
  31. GRB 230301A: Fermi GBM Final Real-time Localization
  32. GRB 230228A: Miryang Arirang Astronomical Observatory (MAAO) 0.7-m telescope optical upper limit
  33. GRB 230228A: Swift detection of a possibly short burst
  34. GRB 230227A: Fermi GBM Final Real-time Localization
  35. GRB 230222A: Fermi GBM Final Real-time Localization
  36. GRB 230217A: Swift-XRT afterglow detection
  37. GRB 230217A: AstroSat CZTI detection
  38. GRB 230217A: Gemini South optical upper limits
  39. GRB 230216B: CALET Gamma-Ray Burst Monitor detection
  40. GRB 230220B: Fermi GBM Final Real-time Localization
  41. IceCube-230220A - IceCube observation of a high-energy neutrino candidate
  42. GRB 230220A: MAXI/GSC detection
  43. Konus-Wind detection of GRB 230217A
  44. GRB 230218A: Fermi GBM Final Real-time Localization
  45. GRB 230217A: AGILE/MCAL detection
  46. GRB 230207B: CALET Gamma-Ray Burst Monitor detection
  47. GRB 230216B: AstroSat CZTI detection
  48. GRB 230217A: Swift detection of a short burst
  49. GRB 230217A: Fermi GBM Final Real-time Localization
  50. IceCube-230217A - IceCube observation of a high-energy neutrino candidate track-like event
  51. GRB 230216A: Swift detection of a burst
  52. GRB 230215A: Fermi GBM Final Real-time Localization
  53. GRB 230209B: AGILE detection
  54. IPN triangulation of GRB 230209B
  55. GRB 230204B: CALET Gamma-Ray Burst Monitor detection
  56. GRB 230204B: ATCA radio detection
  57. Outburst from LS V +44 17 / RX J0440.9+4431: Transient detection by GRBAlpha
  58. GRB 230211A: Fermi GBM Final Real-time Localization
  59. GRB 230209B: Swift/BAT-GUANO detection outside the coded FOV
  60. Swift Trigger 1153670 is probably not a GRB
  61. GRB 230210A: Fermi GBM Final Real-time Localization
  62. GRB 230209B: Fermi GBM Final Real-time Localization
  63. GRB 230209A: Fermi GBM Final Real-time Localization
  64. GRB 230207B: Detection by GRBAlpha
  65. GRB 230205A: possible host galaxy detection with the Schmidt - Asiago telescope
  66. GRB 230204B: MASTER early OT detection
  67. GRB 230208A: Fermi GBM Final Real-time Localization
  68. GRB 230207B: Swift/BAT-GUANO detection outside the coded FOV
  69. ZTF23aabmzlp/AT2023azs: Neil Gehrels Swift Observatory X-ray observations
  70. GRB 230207B: AGILE detection of a burst
  71. GRB 230207A: Fermi GBM Final Real-time Localization
  72. GRB 230204B: Fermi GBM detection
  73. GRB 230204B: Swift-XRT afterglow detection
  74. GRB 230204B: 3.6m DOT optical observation
  75. GRB 230204B: VLT/X-shooter redshift
  76. GRB 230204B: ATLAS detection of the optical afterglow and a projected location in a nearby galaxy group
  77. GRB 230205A: BOOTES-5/JGT early optical upper limit
  78. GRB 230204B: Detection by GRBAlpha
  79. GRB 230204B: AGILE detection
  80. GRB 230205A: Swift detection of a burst
  81. GRB 230204B: AstroSat CZTI detection
  82. GRB 230204B: Swift/BAT-GUANO detection outside the coded FOV
  83. GRB 230204B: MAXI/GSC detection
  84. GRB 230204A: Swift detection of a possible burst (or possible transient Swift J1552.8-5055)
  85. ZTF23aabmzlp/AT2023azs: Lulin 1m LOT optical observations
  86. ZTF23aabmzlp/AT2023azs: VLA radio detection
  87. ZTF23aaarlti/AT2023avj: AMI-LA radio detection
  88. ZTF23aabmzlp/AT2023azs: AMI-LA radio upper limit
  89. GRB 230201B: Fermi GBM Final Real-time Localization
  90. GRB 230126A: Detection by VZLUSAT-2
  91. IceCube-230201A - IceCube observation of a high-energy neutrino candidate track-like event
  92. GRB 221009A: radio afterglow detection with the EVN
  93. GRB 230201A: Fermi GBM Final Real-time Localization
  94. ZTF23aabmzlp/AT2023azs: LCOGT Optical Detection
  95. AT2023avj: X-ray Detection with Swift/XRT
  96. ZTF23aabmzlp/AT2023azs: 1.3m DFOT optical observations
  97. GRB 230129A: AstroSat CZTI detection
  98. GRB 230128A: AstroSat CZTI detection
  99. GRB 230130A: Fermi GBM Final Real-time Localization
  100. ZTF23aaarlti/AT2023avj: VLA radio detection

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