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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"

37562 results found.

  1. GRB 251205A: Zeiss-1000 Koshka observatory optical observations
  2. GRB 251205A: COLIBRÍ optical observations
  3. GRB 251205A: GOTO optical afterglow detection
  4. GRB 251205A: NOT optical observations
  5. GRB 251205A: GTC/OSIRIS+ redshift z = 1.100
  6. GRB 251205A: Enhanced Swift-XRT position
  7. Swift GRB 251205A : MASTER OT detection with host galaxy
  8. GRB 251205A: Swift detection of a burst with an optical afterglow
  9. GRB 251126B: Fermi GBM Final Localization
  10. GRB 251203A: Insight-HXMT/HE detection
  11. GRB 251203C: SVOM/ECLAIRs refined analysis
  12. GRB 251202A / EP251202a: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 40-cm and 1-m telescopes at McDonald Observatory
  13. GRB 251203C: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  14. GRB 251202A: SVOM/GRM observation
  15. GRB 251203A: GECAM-B observation of a burst
  16. GRB 251203A: SVOM/GRM observation
  17. GRB 251201B: SALT spectroscopic redshift z = 1.599
  18. GRB 251203C: J-band observations with WINTER
  19. GRB 251129B: Glowbug gamma-ray detection of a short burst
  20. GRB 251203A: AstroSat CZTI detection
  21. Fermi Gamma-ray Burst Monitor trigger 786496343/251203967 is not a GRB
  22. GRB 251203C: LCO optical afterglow confirmation
  23. GRB 251203C: SVOM/VT optical counterpart
  24. GRB 251203C: EP-FXT follow-up observation
  25. GRB 251129A/EP251129a : SVOM/ECLAIRs refined analysis
  26. GRB 251129B: GECAM-B observation of a burst
  27. GRB 251203B: Swift-XRT observations
  28. GRB 251203B: confirmation of a stellar flare by BOOTES-2
  29. GRB 251203B : SVOM trigger sb25120304 is not a GRB
  30. GRB 251203C: LCO optical upper limits
  31. GRB 251203B: LCO optical upper limits
  32. GRB 251203B: SVOM/VT optical observation
  33. GRB 251202A / EP251202a: Liverpool Telescope optical follow-up observations
  34. GRB 251203C: SVOM detection of a burst
  35. GRB 251203B: SVOM detection of a burst
  36. GRB 251129A / EP251129a: SVOM/VT optical color bluer
  37. GRB 251201B: Insight-HXMT/HE detection
  38. EP251202a / GRB 251202A: Insight-HXMT/HE detection
  39. GRB 251203A: Fermi GBM Final Real-time Localization
  40. EP251202a / GRB251202A: AstroSat CZTI detection
  41. GRB 251202A / EP251202a: SVOM/VT optical observation
  42. GRB 251201B: Fermi GBM Observation
  43. EP251202a/GRB 251202A: KAIT optical observations
  44. Fermi GRB 251202B: Global MASTER-Net observations report
  45. GRB 251202B: Fermi GBM Final Real-time Localization
  46. IPN triangulation of GRB 251129B (short/hard)
  47. GRB251129A/EP251129a: Swift UVOT detection
  48. GRB 251129B: AstroSat CZTI detection
  49. GRB 251202A: Fermi GBM Observation
  50. GRB 251202A: Swift/UVOT Detection
  51. GRB 251201B: Kilonova-Catcher optical afterglow detection
  52. GRB 251201B: Swift/UVOT Detection
  53. GRB 251130B: Glowbug gamma-ray detection
  54. GRB 251201B: GECAM-B observation of a long burst
  55. GRB 251122A/EP251122a: CrAO ZTSh optical observations
  56. Fermi-LAT Gamma-ray Observations of IceCube-251130A
  57. EP251202a / GRB 251202A: LCO r- and i-band optical detection
  58. GRB 251202A: GOTO optical afterglow detection
  59. EP251202a/GRB 251202A: refined analysis of the EP-WXT observations
  60. GRB 251201A: GECAM-B observation of a burst
  61. GRB 251126A: SAO RAS optical marginal detection
  62. GRB 251202A: Swift-XRT afterglow detection
  63. EP251129a/GRB 251129A: NOWT Detection
  64. GRB 251126A: SVOM/VT optical observation
  65. EP251202a / GRB 251202A: NOT spectroscopic redshift z = 2.785
  66. Fermi GRB 251202A: Global MASTER-Net observations report
  67. EP251202a/GRB 251202A: Einstein Probe detection of an X-ray transient
  68. GRB 251201B: Swift-XRT refined Analysis
  69. GRB 251202A: Fermi GBM Final Real-time Localization
  70. GRB 251201A: SVOM/GRM observation of a burst
  71. GRB 251201B: SVOM/VT optical fading
  72. Swift GRB 251201B : MASTER optical counterpart detection
  73. GRB 251201B: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 1-m telescope at Sutherland Observatory
  74. Swift GRB 251201B: Global MASTER-Net observations report
  75. GRB 251201B: Enhanced Swift-XRT position
  76. EP251118a: Mondy, CrAO, Assy and SAO RAS/Zeiss-1000 optical observations
  77. GRB 251130B: AstroSat CZTI detection
  78. GRB 251201B: Swift detection of a burst with an optical counterpart
  79. GRB 251201B: Fermi GBM Final Real-time Localization
  80. EP251130a: Mondy optical observations
  81. EP251130a: SAO RAS optical observations
  82. EP251130a: KAIT optical observations
  83. GRB 251201A: MAXI/GSC detection
  84. Fermi GRB 251130B: Global MASTER-Net observations report
  85. GRB 251127A: SVOM/GRM observation
  86. IceCube-251130A - IceCube observation of a high-energy neutrino candidate track-like event
  87. GRB 251130B: Fermi GBM Final Localization Correction
  88. GRB 251130B: Fermi GBM Final Real-time Localization
  89. EP251129a/GRB 251129A: EP-FXT follow-up observations
  90. GRB 251130A: Fermi GBM Final Real-time Localization
  91. GRB 251129A / EP251129a: GTC/OSIRIS+ spectroscopic redshift z = 1.460
  92. GRB 251129A / EP251129a: OSN and CAHA optical follow-up
  93. GRB 251128A: AstroSat CZTI detection
  94. GRB 251129A / EP251129a: SAO RAS optical observations
  95. GRB 251126A: SAO RAS optical observations
  96. GRB 251128A: GECAM-B detection
  97. GRB 251128A: SVOM/GRM observation of a long burst
  98. GRB 251128A: Insight-HXMT/HE detection
  99. SVOM GRB 251129A : MASTER optical counterpart detection
  100. GRB 251129A: Swift-XRT afterglow detection

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