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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

11621 results found.

  1. GRB 251209A: Fermi GBM observation
  2. GRB 251209A: AstroSat CZTI detection
  3. IceCube-251210A - IceCube observation of a high-energy neutrino candidate track-like event
  4. GRB 251208A: AstroSat CZTI detection
  5. Fermi GBM Sub-Threshold Detection of GRB 251205A
  6. GRB 251208A: Glowbug gamma-ray detection
  7. GRB 251208B: COLIBRÍ optical upper limits
  8. GRB 251208C: GECAM-B observation of a short burst
  9. GRB 251208A: GECAM-B observation of a short burst
  10. Fermi GRB 251209A: Global MASTER-Net observations report
  11. Fermi GRB 251208C: Global MASTER-Net observations report
  12. GRB 251208B: Swift-XRT afterglow detection
  13. GRB 251209A: Fermi GBM Final Real-time Localization
  14. GRB 251208B: Fermi GBM Observation
  15. GRB 251208B: GROWTH-India Telescope optical upper limits
  16. GRB 251208A: SVOM/GRM observation of a short burst
  17. GRB 251208C: SVOM/GRM observation of a short burst
  18. GRB 251208B: Swift ToO observations
  19. GRB 251208B: Fermi-LAT detection
  20. GRB 251208B: Swift/BAT-GUANO arcminute localization of a burst
  21. GRB 251208C: Fermi GBM Final Real-time Localization
  22. GRB 251208B: Fermi GBM Final Real-time Localization
  23. GRB 251208A: Fermi GBM Final Real-time Localization
  24. Konus-Wind detection of GRB 251118A
  25. GRB 251126B: Fermi GBM Final Localization
  26. GRB 251203A: Insight-HXMT/HE detection
  27. GRB 251202A / EP251202a: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 40-cm and 1-m telescopes at McDonald Observatory
  28. GRB 251202A: SVOM/GRM observation
  29. GRB 251203A: GECAM-B observation of a burst
  30. GRB 251203A: SVOM/GRM observation
  31. GRB 251201B: SALT spectroscopic redshift z = 1.599
  32. GRB 251203A: AstroSat CZTI detection
  33. Fermi Gamma-ray Burst Monitor trigger 786496343/251203967 is not a GRB
  34. GRB 251202A / EP251202a: Liverpool Telescope optical follow-up observations
  35. GRB 251201B: Insight-HXMT/HE detection
  36. EP251202a / GRB 251202A: Insight-HXMT/HE detection
  37. GRB 251203A: Fermi GBM Final Real-time Localization
  38. EP251202a / GRB251202A: AstroSat CZTI detection
  39. GRB 251202A / EP251202a: SVOM/VT optical observation
  40. GRB 251201B: Fermi GBM Observation
  41. EP251202a/GRB 251202A: KAIT optical observations
  42. Fermi GRB 251202B: Global MASTER-Net observations report
  43. GRB 251202B: Fermi GBM Final Real-time Localization
  44. GRB 251202A: Fermi GBM Observation
  45. GRB 251201B: Kilonova-Catcher optical afterglow detection
  46. GRB 251130B: Glowbug gamma-ray detection
  47. GRB 251201B: GECAM-B observation of a long burst
  48. Fermi-LAT Gamma-ray Observations of IceCube-251130A
  49. EP251202a / GRB 251202A: LCO r- and i-band optical detection
  50. GRB 251202A: GOTO optical afterglow detection
  51. EP251202a / GRB 251202A: NOT spectroscopic redshift z = 2.785
  52. Fermi GRB 251202A: Global MASTER-Net observations report
  53. EP251202a/GRB 251202A: Einstein Probe detection of an X-ray transient
  54. GRB 251202A: Fermi GBM Final Real-time Localization
  55. GRB 251201B: SVOM/VT optical fading
  56. Swift GRB 251201B : MASTER optical counterpart detection
  57. GRB 251201B: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 1-m telescope at Sutherland Observatory
  58. GRB 251130B: AstroSat CZTI detection
  59. GRB 251201B: Fermi GBM Final Real-time Localization
  60. Fermi GRB 251130B: Global MASTER-Net observations report
  61. GRB 251127A: SVOM/GRM observation
  62. IceCube-251130A - IceCube observation of a high-energy neutrino candidate track-like event
  63. GRB 251130B: Fermi GBM Final Localization Correction
  64. GRB 251130B: Fermi GBM Final Real-time Localization
  65. GRB 251130A: Fermi GBM Final Real-time Localization
  66. GRB 251128A: AstroSat CZTI detection
  67. GRB 251128A: GECAM-B detection
  68. GRB 251128A: SVOM/GRM observation of a long burst
  69. GRB 251128A: Insight-HXMT/HE detection
  70. GRB 251128A: Fermi GBM Observation
  71. GRB 251128A: Swift/BAT-GUANO localization skymap of a burst
  72. Fermi GRB 251128A: Global MASTER-Net observations report
  73. GRB 251127A: Glowbug gamma-ray detection
  74. GRB 251128A: Fermi GBM Final Real-time Localization
  75. GRB 251125B: GECAM-B detection
  76. Fermi GRB 251127A: Global MASTER-Net observations report
  77. GRB 251127A: Fermi GBM Final Real-time Localization
  78. GRB 251121A: Fermi GBM Observation
  79. GRB 251125B: COLIBRÍ further observations and photometric redshift upper limit of z < 3
  80. GRB 251125B: COLIBRÍ observations of fading of the MASTER OT candidate
  81. Fermi GRB 251125B : MASTER OT J155558.56+581224.1 optical counterpart discovery
  82. Fermi GRB 251125B: Global MASTER-Net observations report
  83. GRB 251125B: Fermi GBM Final Real-time Localization
  84. Fermi GRB 251125A: Global MASTER-Net observations report
  85. GRB 251125A: Fermi GBM Final Real-time Localization
  86. GRB 251124A: Fermi GBM Localization by automated pipeline
  87. GRB 251122B: Fermi GBM Final Localization
  88. Fermi GRB 251124a: Global MASTER-Net observations report
  89. GRB 251124a: Fermi GBM Final Localization
  90. GRB 251121A: Swift/BAT-GUANO localization skymap of a short burst
  91. GRB 251121A: Glowbug gamma-ray detection of a likely short burst
  92. GRB 251115A: Fermi GBM Observation
  93. GRB 251121A: Fermi GBM Final Real-time Localization
  94. Fermi Gamma-ray Burst Monitor trigger 785388351 / 251121143 is not a GRB
  95. Fermi trigger No 785388351: Global MASTER-Net observations report
  96. GRB 251118A: Swift/UVOT Detection
  97. GRB 251118A: Glowbug gamma-ray detection
  98. GRB 251118A: Fermi GBM Observation
  99. GRB 251118A: Swift-XRT afterglow detection
  100. GRB 251103A: SVOM/ECLAIRs and SVOM/GRM joint refined analysis

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