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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"

24582 results found.

  1. GRB 230328A: Fermi GBM Final Real-time Localization
  2. GRB 230325A: Swift-BAT refined analysis
  3. GRB 230325A: X-shooter optical afterglow and redshift
  4. GRB 230322B: Swift-BAT refined analysis
  5. GRB 230320B: Fermi GBM Observation
  6. Fermi trigger No 701313046: Global MASTER-Net observations report
  7. Fermi trigger No 701321709: Global MASTER-Net observations report
  8. Konus-Wind detection of GRB 230309A
  9. Konus-Wind detection of GRB 230308A
  10. Konus-Wind detection of GRB 230304B
  11. Swift GRB 230322B: Global MASTER-Net observations report
  12. GRB 230322B: Swift detection of a burst with optical counterpart
  13. GRB 230322A: Fermi GBM Final Real-time Localization
  14. GRB 230320B: GRBAlpha detection
  15. GRB 230321A: CALET Gamma-Ray Burst Monitor detection
  16. Fermi trigger No 701071944: Global MASTER-Net observations report
  17. GRB 230320B: Swift/BAT-GUANO detection outside the coded FOV
  18. Fermi GRB 230320A: Global MASTER-Net observations report
  19. Fermi GRB 230321A: Global MASTER-Net observations report
  20. Fermi trigger No 701058254: Global MASTER-Net observations report
  21. SGR 1806-20: Correction to GCN 33494
  22. GRB 230321A: BALROG localization (Fermi Trigger 701065308 / GRB 230321182)
  23. GRB 230321A: Fermi GBM Final Real-time Localization
  24. GRB 230320A: Fermi GBM Final Real-time Localization
  25. Fermi trigger No 700976129: Global MASTER-Net observations report
  26. GRB 230307A: Continued Gemini-South observations confirm rapid optical fading
  27. IPN triangulation of GRB 230309A
  28. Fermi GRB 230316A: Global MASTER-Net observations report
  29. GRB 230316A: Fermi GBM Final Real-time Localization
  30. IPN triangulation of GRB 230304B
  31. GRB 230307A: Far off-axis NuSTAR detection of the GRB
  32. IPN triangulation of GRB 230308A (short/bright)
  33. Fermi GRB 230314A: Global MASTER-Net observations report
  34. GRB 230314A: Fermi GBM Final Real-time Localization
  35. VZLUSAT-2 detection of SGR 1806-20
  36. GRB 230307A: INTEGRAL upper limit on Hard X-ray afterglow
  37. AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEm-230313A
  38. GRB 230313A: BALROG localization (Fermi Trigger 700400328 / GRB 230313485)
  39. Fermi GRB 230313A: Global MASTER-Net observations report
  40. GRB 230313A: Fermi GBM Final Real-time Localization
  41. GRB 230307A: soft X-ray detection with LEIA
  42. Swift GRB230311.85: Global MASTER-Net observations report
  43. Swift GRB230311.83: Global MASTER-Net observations report
  44. Further improved IPN localization for GRB 230307A
  45. Swift GRB230311.81: Global MASTER-Net observations report
  46. GRB 230307A: SOAR/Goodman detection of the possible host galaxy
  47. Swift GRB230311.84: Global MASTER-Net observations report
  48. Swift GRB230311.82: Global MASTER-Net observations report
  49. Alert from the HAWC Burst Monitor HAWC-230311A
  50. GRB 230308A: CALET Gamma-Ray Burst Monitor detection
  51. GRB 230307A: GECKO optical observations and detections of the afterglow
  52. GRB 230307A: MAXI/GSC upper limit
  53. GRB 230307A: Gemini-South Confirmation of the Optical Afterglow
  54. Fermi GRB 230310A: Global MASTER-Net observations report
  55. GRB 230310A: Fermi GBM Final Real-time Localization
  56. GRB 230307A: AGILE/MCAL analysis
  57. GRB 230308A: Fermi GBM detection
  58. GRB 230307A: Possible optical afterglow
  59. GRB 230307A: ASO-S/HXI detection
  60. GRB 230307A: AstroSat LAXPC detection
  61. GRB 230228A: NUTTelA-TAO / BSTI Optical Limits
  62. GRB 230308A: AGILE/MCAL detection
  63. GRB 230307A: Upper limits from a neutrino search with IceCube
  64. GRB 230307A: Swift-XRT observations
  65. Fermi GRB 230307A: Global MASTER-Net observations report
  66. Konus-Wind detection of GRB 230307A
  67. Improved IPN localization for GRB 230307A
  68. GRB 230307A: VZLUSAT-2 detection
  69. GRB 230304B: CALET Gamma-Ray Burst Monitor detection
  70. Fermi GRB 230308A: Global MASTER-Net observations report
  71. GRB 230308A: BALROG localization (Fermi Trigger 699975152 / GRB 230308564)
  72. GRB 230308A: Fermi GBM Final Real-time Localization
  73. GRB 230307A: Detection by GRBAlpha
  74. GRB 230305A: Detection by GRBAlpha
  75. GRB 230307A: BALROG localization (Fermi Trigger 699896651/ GRB 230307656)
  76. GRB 230307A: possibly the second highest GRB energy fluence ever identified
  77. IPN triangulation of GRB 230307A (long/very bright)
  78. GRB 230307A: AGILE/MCAL detection
  79. GRB 230307A: Fermi GBM Observation of a very bright burst
  80. Solar Orbiter STIX observation of GRB 230307A
  81. IceCube-230306A: Upper limits from a search for additional neutrino events in IceCube
  82. Fermi-LAT gamma-ray observations of IceCube-230306A
  83. GRB 230307A: Fermi GBM detection of a very bright GRB
  84. GRB 230307A: GECAM detection of an extremely bright burst
  85. GRB 230307A: Fermi GBM Final Real-time Localization
  86. Fermi trigger No 699811746: Global MASTER-Net observations report
  87. IceCube-230306A - IceCube observation of a high-energy neutrino candidate
  88. IceCube Alert 230306.46: Global MASTER-Net observations report
  89. GRB 230304B: Detection by GRBAlpha
  90. GRB 230304C: Fermi GBM Final Real-time Localization
  91. GRB 230304B: Fermi GBM Final Real-time Localization
  92. GRB 230304A: Fermi GBM Final Real-time Localization
  93. GRB 230228A: Swift-BAT refined analysis
  94. Fermi GRB 230301B: Global MASTER-Net observations report
  95. GRB 230301B: Fermi GBM Final Real-time Localization
  96. GRB 230228A: Fermi GBM Observation
  97. Fermi trigger No 699294715: Global MASTER-Net observations report
  98. Fermi trigger No 699311646: Global MASTER-Net observations report
  99. GRB 230301A: Fermi GBM Final Real-time Localization
  100. GRB 230228A: Miryang Arirang Astronomical Observatory (MAAO) 0.7-m telescope optical upper limit

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