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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"

36349 results found.

  1. GRB 230307A: further analysis of the Konus-Wind detection and rest-frame energetics
  2. GRB 230307A: good match with kilonova models
  3. GRB 230307A: short mininum variability timescale compatible with a merger origin
  4. GRB 230405B: Swift/UVOT Upper Limits
  5. GRB 230405B: AstroSat CZTI detection
  6. GRB 230405B: Enhanced Swift-XRT position
  7. Swift GRB 230405B: Global MASTER-Net observations report
  8. GRB 230405B: Prompt enhanced Swift-XRT position
  9. GRB 230405B: Swift detection of a burst
  10. GRB 230405B: Fermi GBM Final Real-time Localization
  11. GRB 230307A: JWST observations consistent with the presence of a kilonova
  12. Fermi GRB 230405A: Global MASTER-Net observations report
  13. GRB 230405A: Fermi GBM Final Real-time Localization
  14. GRB 230404A: AstroSat CZTI detection
  15. GRB 230404A: Fermi GBM Final Real-time Localization
  16. GRB 230402A: CALET Gamma-Ray Burst Monitor detection
  17. GRB 230402A: AstroSat CZTI detection
  18. GRB 230328B: Multa observatory optical afterglow observation
  19. GRB 230307A: Chandra late-time detection of the X-ray afterglow
  20. GRB 230228A: detection by GTC of the potential host galaxy
  21. GRB 230328B: Swift/UVOT Detection
  22. GRB 230402A: AGILE detection
  23. Fermi GRB 230402A: Global MASTER-Net observations report
  24. GRB 230402A: Fermi GBM Final Real-time Localization
  25. GRB 230307A: Bad Time Intervals for Fermi GBM data
  26. GRB 230328B : GRANDMA/Kilonova-Catcher optical detection
  27. GRB 230328B: CAHA 2.2m/CAFOS detection
  28. GRB 230328B: 3.6m DOT multiband optical observation
  29. GRB 230330B: Fermi GBM Final Localization
  30. Konus-Wind detection of GRB 230328B
  31. GRB 230328B: GRBAlpha detection
  32. GRB 230330A: Fermi GBM Final Real-time Localization
  33. GRB 230328B: Swift-BAT refined analysis
  34. GRB 230328B: Nanshan/NEXT 2nd optical observation
  35. GRB 230328B NUTTelA-TAO / BSTI Early Measurements
  36. GRB 230328B: Liverpool Telescope afterglow detection
  37. GRB 230328B: OHP/T120 optical observations
  38. GRB 230328B: GIT optical follow-up
  39. GRB 230328B: OASDG optical observations
  40. GRB 230328B: Nanshan/NEXT optical upper limit
  41. GRB 230328B: Swift-XRT refined Analysis
  42. GRB 230328B: AstroSat CZTI detection
  43. GRB 230328B: Fermi GBM observation
  44. GRB 230328B: Mondy, AbAO and Kitab optical observations
  45. GRB 230328B: Enhanced Swift-XRT position
  46. GRB 230328B: Mondy optical afterglow confirmation
  47. GRB 230328B: Swift detection of a burst with an optical afterglow
  48. GRB 230328B: Fermi GBM Final Real-time Localization
  49. Fermi GRB 230328A: Global MASTER-Net observations report
  50. GRB 230328A: Fermi GBM Final Real-time Localization
  51. GRB 230325A: Swift-BAT refined analysis
  52. GRB 230325A: Swift/UVOT Upper Limits
  53. GRB 230325A: X-shooter optical afterglow and redshift
  54. GRB 230325A: Swift-XRT refined Analysis
  55. GRB 230322B: Swift-BAT refined analysis
  56. GRB 230325A: Enhanced Swift-XRT position
  57. GRB 230325A: Prompt enhanced Swift-XRT position
  58. GRB 230325A: Swift detection of a burst
  59. GRB 230320B: Fermi GBM Observation
  60. GRB 230322B: Swift/UVOT Detection
  61. Konus-Wind detection of GRB 230309A
  62. Konus-Wind detection of GRB 230308A
  63. Konus-Wind detection of GRB 230304B
  64. GRB 230322B: Swift-XRT refined Analysis
  65. GRB 230322B: Enhanced Swift-XRT position
  66. Swift GRB 230322B: Global MASTER-Net observations report
  67. GRB 230322B: Swift detection of a burst with optical counterpart
  68. GRB 230322A: Fermi GBM Final Real-time Localization
  69. GRB 230320B: GRBAlpha detection
  70. GRB 230321A: CALET Gamma-Ray Burst Monitor detection
  71. GRB 230320B: CALET Gamma-Ray Burst Monitor detection
  72. GRB 230320B: Swift/BAT-GUANO detection outside the coded FOV
  73. Fermi GRB 230320A: Global MASTER-Net observations report
  74. Fermi GRB 230321A: Global MASTER-Net observations report
  75. GRB 230321B: AstroSat CZTI detection
  76. GRB 230320B: AstroSat CZTI detection
  77. GRB 230321A: BALROG localization (Fermi Trigger 701065308 / GRB 230321182)
  78. GRB 230321A: Fermi GBM Final Real-time Localization
  79. GRB 230320A: Fermi GBM Final Real-time Localization
  80. GRB 230314A: TURBO Optical Upper Limit
  81. GRB 230307A: Continued Gemini-South observations confirm rapid optical fading
  82. IPN triangulation of GRB 230309A
  83. Fermi GRB 230316A: Global MASTER-Net observations report
  84. GRB 230304D: AstroSat CZTI detection
  85. GRB 230316A: Fermi GBM Final Real-time Localization
  86. IPN triangulation of GRB 230304B
  87. GRB 230313A: AstroSat CZTI detection
  88. GRB 230307A: Far off-axis NuSTAR detection of the GRB
  89. IPN triangulation of GRB 230308A (short/bright)
  90. Fermi GRB 230314A: Global MASTER-Net observations report
  91. GRB 230307A: ATCA radio detection
  92. GRB 230314A: Fermi GBM Final Real-time Localization
  93. VZLUSAT-2 detection of SGR 1806-20
  94. GRB 230307A: INTEGRAL upper limit on Hard X-ray afterglow
  95. GRB 230307A: Swift/UVOT detection
  96. GRB 230313A: BALROG localization (Fermi Trigger 700400328 / GRB 230313485)
  97. Fermi GRB 230313A: Global MASTER-Net observations report
  98. GRB 230313A: Fermi GBM Final Real-time Localization
  99. GRB 230307A: soft X-ray detection with LEIA
  100. GRB 230307A: Swift-XRT afterglow detection

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