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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

11529 results found.

  1. IPN triangulation of GRB 210624A (short)
  2. GRB 210619B: ASIM observation
  3. Fermi trigger No 646189108: Global MASTER-Net observations report
  4. Fermi GBM observation of a bright burst in the direction of SGR 1935+2154
  5. Fermi trigger No 646194855: Global MASTER-Net observations report
  6. Fermi GRB 210622B: Global MASTER-Net observations report
  7. GRB 210622A: Fermi GBM detection
  8. GRB 210619B: SPI-ACS/INTEGRAL observations
  9. GRB 210622A: Swift/BAT-GUANO detection and arcminute localization of a long burst
  10. GECAM detection of GRB 210622B
  11. GRB 210622B: Fermi GBM Final Real-time Localization
  12. GRB 210622A: Fermi GBM Final Real-time Localization
  13. GRB 210619B: 1.5m OSN optical observation
  14. Fermi GRB 210621A: Global MASTER-Net observations report
  15. GRB 210621A: Fermi GBM Final Real-time Localization
  16. GRB 210619B: CALET Gamma-Ray Burst Monitor detection
  17. GRB 210619B: SRG/ART-XC detection
  18. GRB 210619B: Fermi GBM detection
  19. GRB 210619B: Xinglong TNT optical observations
  20. Konus-Wind detection of GRB 210619B
  21. GRB 210619B: CAHA 2.2m photometric monitoring
  22. GRB 210619B: Liverpool Telescope r'-band observations
  23. GRB 210619B: Fermi-LAT detection
  24. Fermi trigger No 645857659: Global MASTER-Net observations report
  25. GECAM detection of GRB 210619B
  26. GRB 210619A: BALROG localization (Fermi Trigger 645799548 / GRB 210619532)
  27. GRB 210619A: Fermi GBM Final Real-time Localization
  28. GRB 210618A: BOOTES-2/TELMA optical upper limit
  29. GRB 210618A: Fermi GBM observation
  30. GRB 210618A: DDOTI upper limit for the optical afterglow
  31. GRB 210618A: Fermi GBM Final Real-time Localization
  32. Fermi trigger No 645485036: Global MASTER-Net observations report
  33. GRB 201008A: Fermi GBM observation
  34. GRB 210323B: Fermi GBM observation
  35. Fermi GRB 210615A: Global MASTER-Net observations report
  36. GRB 210615A: Fermi GBM Final Real-time Localization
  37. GRB 210610A: Fermi GBM observations
  38. GRB 210421B: Fermi GBM detection
  39. GRB 201228B: Fermi GBM observation
  40. GRB 210606A: Fermi GBM detection
  41. GRB 210605B: Fermi GBM detection
  42. GRB 210610B: Fermi GBM detection
  43. Fermi trigger No 645047470: Global MASTER-Net observations report
  44. GRB 210610B: BALROG localization (Fermi Trigger 645047470 / GRB 210610827)
  45. GRB 210605A: CALET Gamma-Ray Burst Monitor detection
  46. Konus-Wind detection of GRB 210606B
  47. Fermi-LAT Gamma-ray Observations of IceCube-210608A
  48. IceCube-210608A: not observable by Fermi-GBM
  49. IPN triangulation of GRB 210606B
  50. IceCube-210608A: IceCube observation of a high-energy neutrino candidate track-like event
  51. Fermi Gamma-ray Burst Monitor trigger 644793834 / 210607892 is not a GRB
  52. Fermi trigger No 644793834: Global MASTER-Net observations report
  53. GRB 210606B: Fermi GBM detection
  54. Konus-Wind detection of GRB 210605A (short/hard)
  55. IPN triangulation of GRB 210605A (short)
  56. GRB 210606B: AGILE detection
  57. GRB 210606A: 1.5m OSN optical upper limit
  58. GRB 210606B: BALROG localization (Fermi Trigger 644712030 / GRB 210606945)
  59. GRB 210606B: GECAM detection
  60. Fermi trigger No 644712030: Global MASTER-Net observations report
  61. Fermi GRB 210606A: DDOTI Upper Limits on the Afterglow
  62. GRB 210606A: Swift/BAT-GUANO detection and arcminute localization
  63. Fermi GRB 210606A: Global MASTER-Net observations report
  64. GRB 210606A: Fermi GBM Final Real-time Localization
  65. GRB 210605B: Swift/BAT-GUANO detection and arcminute localization
  66. GRB 210605B: Fermi GBM Final Real-time Localization
  67. Fermi GRB 210605A: Global MASTER-Net observations report
  68. GRB 210605A: Fermi GBM Final Real-time Localization
  69. Fermi GBM Sub-Threshold Detection of new Swift SGR J1555.2-5402
  70. Fermi trigger No 644449593: Global MASTER-Net observations report
  71. GRB 210602B: GECAM detection
  72. GRB 210529A: GECAM detection
  73. Fermi trigger No 644359567: Global MASTER-Net observations report
  74. Fermi GRB 210601A: Global MASTER-Net observations report
  75. GRB 210601A: Fermi GBM Final Real-time Localization
  76. IPN triangulation of GRB 210531A
  77. GRB210529B: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 644025222)
  78. GRB 210531A: AstroSat CZTI detection
  79. Fermi trigger No 644155206: Global MASTER-Net observations report
  80. GRB 210531A: AGILE/MCAL detection (Fermi Trigger 644155206 / GRB 210531500)
  81. GRB 210531A: BALROG localization (Fermi Trigger 644155206 / GRB 210531500)
  82. GRB 210529B: DDOTI Upper Limits on the Afterglow
  83. Fermi GRB 210529A: Global MASTER-Net observations report
  84. Fermi GRB 210529B: Global MASTER-Net observations report
  85. GRB 210529B: Fermi GBM Final Real-time Localization
  86. GRB 210529A: Fermi GBM Final Real-time Localization
  87. GRB 210528A: Fermi GBM detection
  88. GRB 210528A: AstroSat CZTI detection
  89. Fermi GRB 210528A: Global MASTER-Net observations report
  90. GRB 210528A: BALROG localization (Fermi Trigger 643903431 / GRB 210528586)
  91. GRB 210528A: Fermi GBM Final Real-time Localization
  92. Fermi GRB 210524B: DDOTI Upper Limits on the Afterglow
  93. Konus-Wind detection of GRB 210524A
  94. IPN triangulation of GRB 210524A
  95. Fermi trigger No 643548039: Global MASTER-Net observations report
  96. GRB 210524B: Fermi GBM Final Real-time Localization
  97. GRB 210524A: BALROG localization (Fermi Trigger 643525204 / GRB 210524208)
  98. Fermi GRB 210524A: Global MASTER-Net observations report
  99. GRB 210524A: Fermi GBM Final Real-time Localization
  100. GRB 210522A: GECAM detection

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