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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"

37350 results found.

  1. IPN triangulation of GRB 240411A
  2. GRB 240414A : MITSuME Akeno optical upper limits
  3. GRB 240414A: Redshift confirmation from GTC/OSIRIS+
  4. GRB 240414A : OHP/T193 redshift determination
  5. GRB 240414A : OHP/T193 optical counterpart detection
  6. GRB 240414A: Swift detection of a burst
  7. LIGO/Virgo/KAGRA S240413p: Zwicky Transient Facility observations
  8. GRB 240411B: CrAO/ZTSh optical observations
  9. GRB 240411B: Kinder observations with Lulin observatory
  10. GRB 240411B: HiPERCAM/GTC observation
  11. GRB 240411B: Swift-BAT refined analysis
  12. GRB 240411B: Swift-XRT refined Analysis
  13. GRB 240411B: 1.3m DFOT Optical observations
  14. GRB 240411A: GRBAlpha detection
  15. GRB 240411B: OHP/T193 optical observations
  16. GRB 240405A: Glowbug gamma-ray detection
  17. GRB 240411B: Enhanced Swift-XRT position
  18. GRB 240411B: LCO optical afterglow detection
  19. GRB 240411B: Swift detection of a burst
  20. GRB 240408B: GRBAlpha detection
  21. GRB 240411A: Fermi GBM Final Real-time Localization
  22. EP240408a: Upper limits from GECAM-B Observation
  23. GRB 240405A: GRBAlpha detection
  24. GRB 240408B: AstroSat CZTI detection
  25. Fermi GRB 240408A: Global MASTER-Net observations report
  26. GRB 240408A: Fermi GBM Final Real-time Localization
  27. GRB 240407A: BALROG localization (Fermi Trigger 734144396 / GRB 240407042)
  28. GRB 240402C: CALET Gamma-Ray Burst Monitor detection
  29. Fermi GRB 240407A: Global MASTER-Net observations report
  30. GRB 240407A: Fermi GBM Final Real-time Localization
  31. LXT 240402A/GRB 240402B: rest-frame energetics from Konus-Wind observation
  32. Fermi GRB 240405B: Global MASTER-Net observations report
  33. GRB 240405B: Fermi GBM Final Real-time Localization
  34. GRB 240402C: Glowbug gamma-ray detection
  35. GRB 240405A: Fermi GBM Final Real-time Localization
  36. GRB 240402C: GRBAlpha detection
  37. GRB 240331A: GRBAlpha detection
  38. LXT 240402A/GRB 240402B: GECAM-C refined analysis
  39. GRB 240403B: Glowbug gamma-ray detection
  40. GRB 240403A: Glowbug gamma-ray detection
  41. LXT 240402A/GRB 240402B: Glowbug gamma-ray detection
  42. Konus-Wind detection of LXT 240402A/GRB 240402B
  43. GRB/FXT 240402B: Kinder optical counterpart candidate
  44. GRB/FXT 240402B: VLT/FORS2 optical afterglow candidate
  45. GRB 240403A: Fermi GBM Detection
  46. LXT 240402A: EP-FXT detection of the X-ray afterglow
  47. Fermi GRB 240404A: Global MASTER-Net observations report
  48. GRB 240404A: Fermi GBM Final Real-time Localization
  49. GRB 240402B: GWAC-F50A optical upper limit
  50. GRB 240402B: GECAM-C detection
  51. GRB 240403A: BALROG localization (Fermi Trigger 733838255 / GRB 240403498)
  52. Fermi GRB 240402A: Global MASTER-Net observations report
  53. GRB 240402A: Fermi GBM Final Real-time Localization
  54. X-ray transient EP240331a: Kinder optical upper limits
  55. IBAS Alert n.10651 not a GRB
  56. GRB 240329A: Glowbug gamma-ray detection
  57. GRB 240324A: AstroSat CZTI detection of a short burst
  58. GRB 240331A: AstroSat CZTI detection
  59. GRB 240329A: AstroSat CZTI detection
  60. GRB 240331A: Fermi GBM Final Real-time Localization
  61. GRB 240329A: GRBAlpha detection
  62. Fermi GRB 240329A: Global MASTER-Net observations report
  63. GRB 240329A: BALROG localization (Fermi Trigger 733441392 / GRB 240329905)
  64. GRB 240329A: Fermi GBM Final Real-time Localization
  65. Fermi GRB 240328B: Global MASTER-Net observations report
  66. Fermi GRB 240328A: Global MASTER-Net observations report
  67. GRB 240328C: Glowbug gamma-ray detection
  68. GRB 240328B: Fermi GBM Final Real-time Localization
  69. GRB 240328A: Fermi GBM Final Real-time Localization
  70. X-ray transient EP 240315a: Second epoch Chandra observations
  71. Transient EPW20240219aa: REM optical/NIR further observations
  72. GRB 240320A: Glowbug gamma-ray detection
  73. GRB 240318A: Fermi GBM Observation
  74. Fermi GRB 240320A: Global MASTER-Net observations report
  75. Konus-Wind detection of GRB 240315C (possible counterpart of EP240315a)
  76. GRB 240315C / X-ray transient EP240315a: Swift/BAT detection
  77. GRB 240318A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  78. GRB 240320A: Fermi GBM Final Real-time Localization
  79. IPN triangulation of GRB 240315C (consistent with a fast X-ray transient EP240315a)
  80. GRB 240317B: Swift/BAT-GUANO Angular Error Correction
  81. Fermi Gamma-ray Burst Monitor trigger 732299243/240316686 is not a GRB
  82. GRB 240318A: Glowbug gamma-ray detection
  83. GRB 240317C: Glowbug gamma-ray detection
  84. GRB 240318B: Glowbug gamma-ray detection
  85. GRB 240317B: Fermi GBM Observation
  86. X-ray transient EP240315a/AT2024eju: TShAO (Zeiss-1000) observatory optical upper limit
  87. Fermi GRB 240318A: Global MASTER-Net observations report
  88. GRB 240318A: Fermi GBM Final Real-time Localization
  89. GRB 240317B: Swift/BAT-GUANO arcminute localization of a burst
  90. GRB 240317A: AstroSat CZTI detection
  91. GRB 240315B: AstroSat CZTI detection
  92. X-ray transient EP240315a: Kitab observatory optical upper limitns
  93. X-ray transient EP240315a: Montarrenti Observatory optical upper limit
  94. Fermi GRB 240317B: Global MASTER-Net observations report
  95. Fermi GRB 240317A: Global MASTER-Net observations report
  96. GRB 240317B: Fermi GBM Final Real-time Localization
  97. GRB 240317A: Fermi GBM Final Real-time Localization
  98. X-ray transient EP240315a: Kinder follow-up observations for AT 2024eju with Lulin observatory
  99. X-ray transient EP240315a: VLT/X-shooter spectroscopic redshift of z = 4.859
  100. GRID detection of GRB 240306A

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