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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"

24581 results found.

  1. GRB 230325A: Swift-BAT refined analysis
  2. GRB 230325A: X-shooter optical afterglow and redshift
  3. GRB 230322B: Swift-BAT refined analysis
  4. GRB 230320B: Fermi GBM Observation
  5. Fermi trigger No 701313046: Global MASTER-Net observations report
  6. Fermi trigger No 701321709: Global MASTER-Net observations report
  7. Konus-Wind detection of GRB 230309A
  8. Konus-Wind detection of GRB 230308A
  9. Konus-Wind detection of GRB 230304B
  10. Swift GRB 230322B: Global MASTER-Net observations report
  11. GRB 230322B: Swift detection of a burst with optical counterpart
  12. GRB 230322A: Fermi GBM Final Real-time Localization
  13. GRB 230320B: GRBAlpha detection
  14. GRB 230321A: CALET Gamma-Ray Burst Monitor detection
  15. Fermi trigger No 701071944: Global MASTER-Net observations report
  16. GRB 230320B: Swift/BAT-GUANO detection outside the coded FOV
  17. Fermi GRB 230320A: Global MASTER-Net observations report
  18. Fermi GRB 230321A: Global MASTER-Net observations report
  19. Fermi trigger No 701058254: Global MASTER-Net observations report
  20. SGR 1806-20: Correction to GCN 33494
  21. GRB 230321A: BALROG localization (Fermi Trigger 701065308 / GRB 230321182)
  22. GRB 230321A: Fermi GBM Final Real-time Localization
  23. GRB 230320A: Fermi GBM Final Real-time Localization
  24. Fermi trigger No 700976129: Global MASTER-Net observations report
  25. GRB 230307A: Continued Gemini-South observations confirm rapid optical fading
  26. IPN triangulation of GRB 230309A
  27. Fermi GRB 230316A: Global MASTER-Net observations report
  28. GRB 230316A: Fermi GBM Final Real-time Localization
  29. IPN triangulation of GRB 230304B
  30. GRB 230307A: Far off-axis NuSTAR detection of the GRB
  31. IPN triangulation of GRB 230308A (short/bright)
  32. Fermi GRB 230314A: Global MASTER-Net observations report
  33. GRB 230314A: Fermi GBM Final Real-time Localization
  34. VZLUSAT-2 detection of SGR 1806-20
  35. GRB 230307A: INTEGRAL upper limit on Hard X-ray afterglow
  36. AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEm-230313A
  37. GRB 230313A: BALROG localization (Fermi Trigger 700400328 / GRB 230313485)
  38. Fermi GRB 230313A: Global MASTER-Net observations report
  39. GRB 230313A: Fermi GBM Final Real-time Localization
  40. GRB 230307A: soft X-ray detection with LEIA
  41. Swift GRB230311.85: Global MASTER-Net observations report
  42. Swift GRB230311.83: Global MASTER-Net observations report
  43. Further improved IPN localization for GRB 230307A
  44. Swift GRB230311.81: Global MASTER-Net observations report
  45. GRB 230307A: SOAR/Goodman detection of the possible host galaxy
  46. Swift GRB230311.84: Global MASTER-Net observations report
  47. Swift GRB230311.82: Global MASTER-Net observations report
  48. Alert from the HAWC Burst Monitor HAWC-230311A
  49. GRB 230308A: CALET Gamma-Ray Burst Monitor detection
  50. GRB 230307A: GECKO optical observations and detections of the afterglow
  51. GRB 230307A: MAXI/GSC upper limit
  52. GRB 230307A: Gemini-South Confirmation of the Optical Afterglow
  53. Fermi GRB 230310A: Global MASTER-Net observations report
  54. GRB 230310A: Fermi GBM Final Real-time Localization
  55. GRB 230307A: AGILE/MCAL analysis
  56. GRB 230308A: Fermi GBM detection
  57. GRB 230307A: Possible optical afterglow
  58. GRB 230307A: ASO-S/HXI detection
  59. GRB 230307A: AstroSat LAXPC detection
  60. GRB 230228A: NUTTelA-TAO / BSTI Optical Limits
  61. GRB 230308A: AGILE/MCAL detection
  62. GRB 230307A: Upper limits from a neutrino search with IceCube
  63. GRB 230307A: Swift-XRT observations
  64. Fermi GRB 230307A: Global MASTER-Net observations report
  65. Konus-Wind detection of GRB 230307A
  66. Improved IPN localization for GRB 230307A
  67. GRB 230307A: VZLUSAT-2 detection
  68. GRB 230304B: CALET Gamma-Ray Burst Monitor detection
  69. Fermi GRB 230308A: Global MASTER-Net observations report
  70. GRB 230308A: BALROG localization (Fermi Trigger 699975152 / GRB 230308564)
  71. GRB 230308A: Fermi GBM Final Real-time Localization
  72. GRB 230307A: Detection by GRBAlpha
  73. GRB 230305A: Detection by GRBAlpha
  74. GRB 230307A: BALROG localization (Fermi Trigger 699896651/ GRB 230307656)
  75. GRB 230307A: possibly the second highest GRB energy fluence ever identified
  76. IPN triangulation of GRB 230307A (long/very bright)
  77. GRB 230307A: AGILE/MCAL detection
  78. GRB 230307A: Fermi GBM Observation of a very bright burst
  79. Solar Orbiter STIX observation of GRB 230307A
  80. IceCube-230306A: Upper limits from a search for additional neutrino events in IceCube
  81. Fermi-LAT gamma-ray observations of IceCube-230306A
  82. GRB 230307A: Fermi GBM detection of a very bright GRB
  83. GRB 230307A: GECAM detection of an extremely bright burst
  84. GRB 230307A: Fermi GBM Final Real-time Localization
  85. Fermi trigger No 699811746: Global MASTER-Net observations report
  86. IceCube-230306A - IceCube observation of a high-energy neutrino candidate
  87. IceCube Alert 230306.46: Global MASTER-Net observations report
  88. GRB 230304B: Detection by GRBAlpha
  89. GRB 230304C: Fermi GBM Final Real-time Localization
  90. GRB 230304B: Fermi GBM Final Real-time Localization
  91. GRB 230304A: Fermi GBM Final Real-time Localization
  92. GRB 230228A: Swift-BAT refined analysis
  93. Fermi GRB 230301B: Global MASTER-Net observations report
  94. GRB 230301B: Fermi GBM Final Real-time Localization
  95. GRB 230228A: Fermi GBM Observation
  96. Fermi trigger No 699294715: Global MASTER-Net observations report
  97. Fermi trigger No 699311646: Global MASTER-Net observations report
  98. GRB 230301A: Fermi GBM Final Real-time Localization
  99. GRB 230228A: Miryang Arirang Astronomical Observatory (MAAO) 0.7-m telescope optical upper limit
  100. Fermi GRB 230227A: Global MASTER-Net observations report

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