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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').
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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"

11559 results found.

  1. Fermi GRB 251216A: Global MASTER-Net observations report
  2. GRB 251202A/EP251202a: Koshka optical upper limit
  3. GRB 251214B: Mondy optical upper limit
  4. GRB 251215A: COLIBRÍ optical upper limit
  5. GRB 251216A: Fermi GBM Final Real-time Localization
  6. Fermi GRB 251215A: Global MASTER-Net observations report
  7. GRB 251214B: 1.6m Mephisto observations with newly installed mosaic cameras
  8. GRB 251215A: Glowbug gamma-ray detection
  9. GRB 251214B: UAFO optical upper limit
  10. GRB 251214B: VLT/X-shooter observations
  11. GRB 251202A: radio detection with the VLA
  12. GRB 251214B: AbAO optical observations
  13. GRB 251214B: LCO detection of the optical counterpart
  14. GRB 251209A: GECAM-B observation of a long burst
  15. GRB 251214B: Fermi GBM Observation
  16. GRB 251209A: Insight-HXMT/HE detection
  17. GRB 251215A: Swift/BAT-GUANO arcminute localization of a burst
  18. GRB 251214B: GECAM-B observation of a long burst
  19. GRB 251214A: AstroSat CZTI detection
  20. GRB 251213A: GECAM-B detection
  21. GRB 251215A: Fermi GBM Final Real-time Localization
  22. GRB 251214B: COLIBRÍ observations of the afterglow
  23. GRB 251214A: GECAM-B observation of a likely long burst
  24. GRB 251214B: 1.3m DFOT optical detection
  25. GRB 251214C: Fermi GBM Final Localization
  26. GRB 251214B : MASTER optical afterglow detection
  27. Fermi trigger No 787396657: Global MASTER-Net observations report
  28. GRB 251214B: SVOM/C-GFT optical observations
  29. EP251214a: COLIBRÍ optical upper limit
  30. GRB 251214B: Fermi GBM Final Real-time Localization
  31. EP251214a: EP-WXT detection of an X-ray transient possibly associated with GRB 251214A
  32. Fermi GRB 251214A: Global MASTER-Net observations report
  33. GRB 251214A: Fermi GBM Final Real-time Localization
  34. GRB 251211B: AstroSat CZTI detection
  35. GRB 251209A: NuSTAR detection of prompt emission
  36. Fermi-LAT Gamma-ray Observations of IceCube-251210A
  37. Fermi GRB 251211B: Global MASTER-Net observations report
  38. GRB 251211B: Fermi GBM Final Real-time Localization
  39. GRB 251211A: Fermi GBM Final Real-time Localization
  40. GRB 251209A: Fermi GBM observation
  41. GRB 251209A: AstroSat CZTI detection
  42. IceCube-251210A - IceCube observation of a high-energy neutrino candidate track-like event
  43. GRB 251208A: AstroSat CZTI detection
  44. Fermi GBM Sub-Threshold Detection of GRB 251205A
  45. GRB 251208A: Glowbug gamma-ray detection
  46. GRB 251208B: COLIBRÍ optical upper limits
  47. GRB 251208C: GECAM-B observation of a short burst
  48. GRB 251208A: GECAM-B observation of a short burst
  49. Fermi GRB 251209A: Global MASTER-Net observations report
  50. Fermi GRB 251208C: Global MASTER-Net observations report
  51. GRB 251208B: Swift-XRT afterglow detection
  52. GRB 251209A: Fermi GBM Final Real-time Localization
  53. GRB 251208B: Fermi GBM Observation
  54. GRB 251208B: GROWTH-India Telescope optical upper limits
  55. GRB 251208A: SVOM/GRM observation of a short burst
  56. GRB 251208C: SVOM/GRM observation of a short burst
  57. GRB 251208B: Swift ToO observations
  58. GRB 251208B: Fermi-LAT detection
  59. GRB 251208B: Swift/BAT-GUANO arcminute localization of a burst
  60. GRB 251208C: Fermi GBM Final Real-time Localization
  61. GRB 251208B: Fermi GBM Final Real-time Localization
  62. GRB 251208A: Fermi GBM Final Real-time Localization
  63. Konus-Wind detection of GRB 251118A
  64. GRB 251126B: Fermi GBM Final Localization
  65. GRB 251203A: Insight-HXMT/HE detection
  66. GRB 251202A / EP251202a: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 40-cm and 1-m telescopes at McDonald Observatory
  67. GRB 251202A: SVOM/GRM observation
  68. GRB 251203A: GECAM-B observation of a burst
  69. GRB 251203A: SVOM/GRM observation
  70. GRB 251201B: SALT spectroscopic redshift z = 1.599
  71. GRB 251203A: AstroSat CZTI detection
  72. Fermi Gamma-ray Burst Monitor trigger 786496343/251203967 is not a GRB
  73. GRB 251202A / EP251202a: Liverpool Telescope optical follow-up observations
  74. GRB 251201B: Insight-HXMT/HE detection
  75. EP251202a / GRB 251202A: Insight-HXMT/HE detection
  76. GRB 251203A: Fermi GBM Final Real-time Localization
  77. EP251202a / GRB251202A: AstroSat CZTI detection
  78. GRB 251202A / EP251202a: SVOM/VT optical observation
  79. GRB 251201B: Fermi GBM Observation
  80. EP251202a/GRB 251202A: KAIT optical observations
  81. Fermi GRB 251202B: Global MASTER-Net observations report
  82. GRB 251202B: Fermi GBM Final Real-time Localization
  83. GRB 251202A: Fermi GBM Observation
  84. GRB 251201B: Kilonova-Catcher optical afterglow detection
  85. GRB 251130B: Glowbug gamma-ray detection
  86. GRB 251201B: GECAM-B observation of a long burst
  87. Fermi-LAT Gamma-ray Observations of IceCube-251130A
  88. EP251202a / GRB 251202A: LCO r- and i-band optical detection
  89. GRB 251202A: GOTO optical afterglow detection
  90. EP251202a / GRB 251202A: NOT spectroscopic redshift z = 2.785
  91. Fermi GRB 251202A: Global MASTER-Net observations report
  92. EP251202a/GRB 251202A: Einstein Probe detection of an X-ray transient
  93. GRB 251202A: Fermi GBM Final Real-time Localization
  94. GRB 251201B: SVOM/VT optical fading
  95. Swift GRB 251201B : MASTER optical counterpart detection
  96. GRB 251201B: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 1-m telescope at Sutherland Observatory
  97. GRB 251130B: AstroSat CZTI detection
  98. GRB 251201B: Fermi GBM Final Real-time Localization
  99. Fermi GRB 251130B: Global MASTER-Net observations report
  100. GRB 251127A: SVOM/GRM observation

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