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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"

14992 results found.

  1. GRB 210529B: Fermi GBM Final Real-time Localization
  2. GRB 210529A: Fermi GBM Final Real-time Localization
  3. GRB 210528A: Fermi GBM detection
  4. GRB 210528A: AstroSat CZTI detection
  5. GRB 210528B: MAXI/GSC detection
  6. GRB 210528A: Fermi GBM Final Real-time Localization
  7. GRB 210527A: Swift detection of a burst
  8. Konus-Wind detection of GRB 210524A
  9. IPN triangulation of GRB 210524A
  10. GRB 210524B: Fermi GBM Final Real-time Localization
  11. GRB 210524A: Fermi GBM Final Real-time Localization
  12. GRB 210522A: GECAM detection
  13. GRB 210521A: MAXI/GSC detection
  14. GRB 210520A: Fermi GBM detection
  15. GRB 210520A: Fermi-LAT detection
  16. GRB 210520A: GECAM detection
  17. GRB 210520A: Fermi GBM Final Real-time Localization
  18. GRB 210517A: KCT optical upper limit
  19. IceCube GCN alert 135302_36915486.amon retraction
  20. IPN triangulation of GRB 210518A
  21. GRB 210519A: Fermi GBM Final Localization
  22. Konus-Wind detection of GRB 210514A
  23. GRB 210518A: Fermi GBM Final Real-time Localization
  24. IceCube-210516A: No significant detection in HAWC
  25. GRB 210517A: VLT/X-shooter optical afterglow and redshift
  26. GRB 210517A: AGILE detection
  27. GRB 210514A: CALET Gamma-Ray Burst Monitor detection
  28. GRB 210517A: Swift detection of a burst
  29. GRB 210516A: Fermi GBM Final Real-time Localization
  30. GRB 210504A: LCO Optical Afterglow Detection
  31. IceCube-210516A - IceCube observation of a high-energy neutrino candidate track-like event
  32. AMON IC_HAWC NuEm-210515A / NuEm-210515B : No neutrino counterpart detected with ANTARES
  33. GRB 210515C: Swift detection of a burst
  34. GRB 210515B: Fermi GBM Final Real-time Localization
  35. GRB 210515A: Fermi GBM Final Real-time Localization
  36. GRB 210514A: Swift detection of a burst
  37. Konus-Wind detection of GRB 210511B
  38. GRB210510A: Optical afterglow candidate from the Zwicky Transient Facility
  39. IPN triangulation of GRB 210511B
  40. Short GRB 210323A: likely host galaxy detection
  41. IPN triangulation of GRB 210427A
  42. GRB 210511B: AGILE detection
  43. GRB 210511B: GECAM detection
  44. GRB 210511B: Fermi GBM Final Real-time Localization
  45. GRB 210511A: Fermi GBM Final Real-time Localization
  46. GRB 201228B: Swift/BAT-GUANO archival detection and arcminute localization
  47. GRB 200716A: Swift/BAT-GUANO archival detection and arcminute localization
  48. GRB 210510A: Fermi GBM Final Real-time Localization
  49. IceCube-210510A - IceCube observation of a high-energy neutrino candidate track-like event
  50. GRB 210509A: BOOTES-4/MET optical upper limit
  51. GRB 210509A: Swift detection of a burst
  52. GRB 210506A: Swift/BAT-GUANO position retraction
  53. IPN triangulation of GRB 210506A
  54. HAWC-210507A: No neutrino counterpart candidates in ANTARES search
  55. Fermi-LAT Gamma-ray Observations of IceCube-210503A and detection of a new gamma-ray source, Fermi J0931.9+3633
  56. GRB 210507A: Fermi GBM Final Real-time Localization
  57. ZTF21aayokph (AT2021lfa): MASTER OT detection 3h befor ZTF
  58. ZTF21aayokph (AT2021lfa): X-ray Detection with Swift/XRT
  59. Lowell Discovery Telescope Observations of ZTF21aayokph (AT2021lfa)
  60. IceCube-210503A: IceCube observation of a high-energy neutrino candidate event
  61. ZTF21aayokph (AT2021lfa): Nanshan/NEXT optical upper limit
  62. GRB 210506A: Swift/BAT-GUANO detection and possible arcminute localization of a short hard burst
  63. ZTF21aayokph (AT2021lfa): Redshift from Gemini South
  64. GRB 210504A: VLT X-shooter redshift
  65. GRB 210424B: AstroSat CZTI detection
  66. ZTF and LT observations of ZTF21aayokph (AT2021lfa), a fast-fading red transient
  67. GRB 210504A: NOT optical afterglow detection
  68. GRB 210504A: AST3-3 YaoAn Optical Upper Limit
  69. GRB 210504A: Swift/UVOT Detection
  70. GRB 210504A: BOOTES-4/MET optical upper limit
  71. GRB 210504A: Swift detection of a burst
  72. GRB 210503A: Fermi GBM Final Real-time Localization
  73. Swift Detection of MAXI J1803-298 including an optical counterpart
  74. GRB 210430A: BOOTES-1 optical limit
  75. GRB 210424B: MITSuME Akeno optical upper limits
  76. GRB 210501A: Fermi GBM Final Real-time Localization
  77. GRB 210430B: Fermi GBM Final Real-time Localization
  78. GRB 210430A: Swift detection of a burst
  79. GRB 210424B: CALET Gamma-Ray Burst Monitor detection
  80. GRB 210413B: Swift/UVOT Observations
  81. Konus-Wind detection of GRB 210424B
  82. GRB 210427A: GECAM detection
  83. GRB 210427A: Fermi GBM Final Real-time Localization
  84. GRB 210422B: Fermi GBM Final Localization
  85. GRB 210425A: GECAM detection
  86. GRB 210424A: Fermi GBM Final Real-time Localization
  87. GRB 210421B: AstroSat CZTI detection
  88. GRB 210421A: GECAM detection
  89. GRB 210421B: AstroSat CZTI detection
  90. GRB 210422A: Swift detection of a burst
  91. GRB 210419B: AstroSat CZTI detection
  92. GRB 210421B: Swift/BAT-GUANO detection and arcminute localization
  93. GRB 210421C: Fermi GBM Final Real-time Localization
  94. GRB 210421B: Fermi GBM Final Localization
  95. GRB 210420B: Ondrejov D50 optical afterglow detection
  96. GRB 210420B: Swift/UVOT Detection
  97. GRB 210420B: DDOTI Detection of the Afterglow
  98. GRB 210420B: Montarrenti Observatory optical afterglow detection
  99. GRB 210421A: Swift detection of a burst
  100. GRB 210420B: AST3-3 YaoAn Optical Observation

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