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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"

37745 results found.

  1. IceCube-231202A - IceCube observation of a high-energy neutrino candidate track-like event
  2. Fermi trigger No 723279695: Global MASTER-Net observations report
  3. The Fermi GBM team reports the detection of a likely SHORT GRB
  4. GRB 231203A: Fermi GBM Final Real-time Localization
  5. GRB 231129C: Swift-XRT afterglow detection
  6. Fermi trigger No 723149952: Global MASTER-Net observations report
  7. GRB 231129C: PROMPT optical upper limits for the MAXI/GSC X-ray counterpart and the MASTER afterglow candidate
  8. GRB 231129A: VZLUSAT-2 detection
  9. GRB 231129B: Swift-XRT observations
  10. GRB 231128A: VZLUSAT-2 detection
  11. GRB 231129C: AGILE detection
  12. GRB 231129A : MITSuME Akeno optical upper limits
  13. GRB 231129C: Swift/BAT-GUANO localization of a burst outside the coded FOV
  14. GRB 231129A: Swift-BAT refined analysis
  15. GRB 231129C: MASTER OT detection
  16. GRB 231129A: BOOTES-5/JGT optical upper limit
  17. GRB 231129C: Fermi-LAT detection
  18. GRB 231129A: JinShan optical upper limit
  19. GRB 231129C: GRBAlpha detection
  20. GRB 231129C: Glowbug gamma-ray detection
  21. GRB 231129C: Swift-XRT observations
  22. GRB 231129A: Swift/UVOT Upper Limits
  23. GRB 231129A: optical upper limit in Mondy observatory
  24. GRB 231129C: GECAM-B detection of a bright burst
  25. GRB 231129C: AstroSat CZTI detection
  26. GRB 231129C: iTelescope OT retraction
  27. GRB 231129C: CALET Gamma-Ray Burst Monitor detection
  28. GRB 231129C: Fermi GBM Observation of a very bright GRB
  29. GRB 231129C: iTelescope likely optical afterglow AT 2023yph discovery
  30. GRB 231129C: Tiled Swift observations
  31. GRB 231127A: GRBAlpha detection
  32. GRB 231129C: MAXI/GSC detection
  33. GRB 231129C: BALROG localization (Fermi Trigger / GRB 231129799)
  34. GRB 231129C: Fermi GBM detection of a very bright burst
  35. GRB 231129A: Enhanced Swift-XRT position
  36. GRB 231129A: Swift-XRT refined Analysis
  37. GRB 231129C: Fermi GBM Final Real-time Localization
  38. Fermi trigger No 722977823: Global MASTER-Net observations report
  39. GRB 231129B: Tiled Swift observations
  40. GRB 231129B: MAXI/GSC detection
  41. Fermi-LAT gamma-ray observations of IceCube-231125A
  42. GRB 231129A: GECAM-C detection of a long burst
  43. GRB 231129A: INTEGRAL detection of a long GRB
  44. GRB 231129A: Swift detection of a burst
  45. GRB 231128A: Fermi GBM Final Real-time Localization
  46. GRB 231123C: Fermi GBM Observation
  47. GRB 231123B: Fermi GBM Observation
  48. GRB 231117A: MeerKAT 1.3GHz detection
  49. GRB 231127A: CALET Gamma-Ray Burst Monitor detection
  50. GRB 231125A: GRBAlpha detection
  51. GRB 231125A: CALET Gamma-Ray Burst Monitor detection
  52. GRB 231127A: AstroSat CZTI detection
  53. GRB 231125A (short): Glowbug gamma-ray detection
  54. GRB 231123B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  55. GRB 231124A: GRBAlpha detection
  56. IceCube-231125A - IceCube observation of a high-energy neutrino candidate track-like event
  57. Fermi trigger No 722653947: Global MASTER-Net observations report
  58. GRB 231125A: AstroSat CZTI detection of a short burst
  59. GRB 231111A: Optical follow-up observations at Terskol, AbAO, Maidanak, Mondy, Assy
  60. GRB 231126A: Fermi GBM Final Real-time Localization
  61. GRB 231123C: Insight-HXMT/HE detection
  62. Fermi trigger No 722460326: Global MASTER-Net observations report
  63. Fermi trigger No 722507896: Global MASTER-Net observations report
  64. GRB 231123C (short): Glowbug gamma-ray detection
  65. GRB 231124A: Glowbug gamma-ray detection
  66. GRB 231123C: Swift/BAT-GUANO detection of a short burst likely outside the coded FOV
  67. Fermi trigger No 722462310: Global MASTER-Net observations report
  68. GRB 231124A: CALET Gamma-Ray Burst Monitor detection
  69. GRB 231115A: XMM-Newton observation
  70. GRB 231124A: Fermi GBM Final Real-time Localization
  71. GRB 231123A: AstroSat CZTI detection
  72. GRB 231117A: Mondy optical observations
  73. GRB 231123C: Fermi GBM Final Real-time Localization
  74. GRB 231123B: Fermi GBM Final Real-time Localization
  75. Fermi trigger No 722400249: Global MASTER-Net observations report
  76. GRB 231118A: REM optical afterglow detection
  77. GRB 231122B: AstroSat CZTI detection
  78. GRB 231122B: CALET Gamma-Ray Burst Monitor detection
  79. GRB 231122B: Swift/BAT-GUANO detection of a long burst outside the coded FOV
  80. GRB 231117A: Chandra afterglow detection
  81. GRB 231123A: Fermi GBM Final Real-time Localization
  82. GRB 231122B: Glowbug gamma-ray detection
  83. GRB 231117A: Continued GTC Observations
  84. Fermi trigger No 722349867: Global MASTER-Net observations report
  85. GRB 231122A: GECAM detection
  86. GRB 231122B: GECAM detection
  87. GRB 231122A: Fermi GBM Final Real-time Localization
  88. GRB 231118A: ATCA detection of radio counterpart
  89. GRB 231117A: Swift/UVOT late time observations
  90. GRB 231117A: GTC Near-Infrared Observations
  91. GRB 231117A: Swift-BAT refined analysis
  92. GRB 231118A: GRBAlpha detection
  93. LIGO/Virgo/KAGRA S231118d: Upper limits from Swift/BAT-GUANO
  94. LIGO/Virgo/KAGRA S231118an: Upper limits from Swift/BAT-GUANO
  95. LIGO/Virgo/KAGRA S231114n: Upper limits from Swift/BAT-GUANO
  96. LIGO/Virgo/KAGRA S231113bb: Upper limits from Swift/BAT-GUANO
  97. GRB 231118A: VZLUSAT-2 detection
  98. GRB 231117A: AMI-LA radio observations
  99. GRB 231118A: Swift-BAT refined analysis
  100. Konus-Wind detection of GRB 231020A

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