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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

28086 results found.

  1. GRB 251208D: LCO analysis of the XRT sources
  2. GRB 251208B: Fermi GBM Observation
  3. GRB 251208B: GROWTH-India Telescope optical upper limits
  4. GRB 251205A: J-band detection with WINTER
  5. GRB 251208D: Swift-XRT observations
  6. GRB 251208A: SVOM/GRM observation of a short burst
  7. GRB 251208C: SVOM/GRM observation of a short burst
  8. GRB 251129A: e-MERLIN C-band observations
  9. LAT GRB251208.43: Global MASTER-Net observations report
  10. GRB 251205A: Liverpool Telescope further optical follow-up observations
  11. GRB 251208D: LCO optical upper limits
  12. SVOM GRB251208D: Global MASTER-Net observations report
  13. GRB 251208B: Fermi-LAT detection
  14. GRB 251208B: Swift/BAT-GUANO arcminute localization of a burst
  15. GRB 251208D: SVOM possible detection of a faint burst
  16. GRB 251205A : MITSuME Akeno optical afterglow candidate detection
  17. GRB 251205A: Liverpool Telescope further optical follow-up observations
  18. SVOM GRB251206.86: Global MASTER-Net observations report
  19. GRB 251205A: GROWTH-India Telescope optical observations
  20. GRB 251205A: Swift-BAT refined analysis
  21. GRB 251205A: Swift-XRT refined Analysis
  22. GRB 251205A: Swift/UVOT Detection
  23. GRB 251205A: Liverpool Telescope optical follow-up observations
  24. GRB 251203C: Swift/UVOT Upper Limit
  25. GRB 251205A: COLIBRÍ optical observations
  26. GRB 251205A: NOT optical observations
  27. GRB 251205A: Enhanced Swift-XRT position
  28. Swift GRB 251205A : MASTER OT detection with host galaxy
  29. GRB 251205A: Swift detection of a burst with an optical afterglow
  30. Swift GRB251205A: Global MASTER-Net observations report
  31. SVOM/sb25120502: SVOM detection of a faint X-ray transient candidate
  32. GRB 251202A / EP251202a: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 40-cm and 1-m telescopes at McDonald Observatory
  33. GRB 251203C: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  34. GRB 251202A: SVOM/GRM observation
  35. GRB 251203A: GECAM-B observation of a burst
  36. GRB 251203A: SVOM/GRM observation
  37. GRB 251203C: J-band observations with WINTER
  38. GRB 251129B: Glowbug gamma-ray detection of a short burst
  39. GRB 251203A: AstroSat CZTI detection
  40. GRB 251203C: SVOM/VT optical counterpart
  41. GRB 251203C: EP-FXT follow-up observation
  42. GRB 251203B: Swift-XRT observations
  43. GRB 251203C: LCO optical upper limits
  44. GRB 251203B: LCO optical upper limits
  45. GRB 251203B: SVOM/VT optical observation
  46. GRB 251202A / EP251202a: Liverpool Telescope optical follow-up observations
  47. SVOM GRB251203.77: Global MASTER-Net observations report
  48. SVOM GRB251203B: Global MASTER-Net observations report
  49. GRB 251203B: SVOM detection of a burst
  50. EP251130a: MAO/AZT-22 optical observations
  51. GRB 251201B: Fermi GBM Observation
  52. EP251202a/GRB 251202A: KAIT optical observations
  53. EP251130a: ULL-ASTRO-MASTER late detection of the optical afterglow with LCO 1-m telescope at Teide Observatory
  54. Fermi GRB 251202B: Global MASTER-Net observations report
  55. IPN triangulation of GRB 251129B (short/hard)
  56. GRB251129A/EP251129a: Swift UVOT detection
  57. GRB 251202A: Fermi GBM Observation
  58. GRB 251202A: Swift/UVOT Detection
  59. GRB 251201B: Kilonova-Catcher optical afterglow detection
  60. GRB 251201B: Swift/UVOT Detection
  61. GRB 251130B: Glowbug gamma-ray detection
  62. EP251130a: continued NOT optical observations indicate steep fading phase
  63. Fermi-LAT Gamma-ray Observations of IceCube-251130A
  64. EP251202a/GRB 251202A: refined analysis of the EP-WXT observations
  65. GRB 251126A: SAO RAS optical marginal detection
  66. GRB 251202A: Swift-XRT afterglow detection
  67. EP251129a/GRB 251129A: NOWT Detection
  68. GRB 251126A: SVOM/VT optical observation
  69. EP251130a: SVOM/VT optical observation
  70. Fermi GRB 251202A: Global MASTER-Net observations report
  71. EP251202a/GRB 251202A: Einstein Probe detection of an X-ray transient
  72. GRB 251201B: Swift-XRT refined Analysis
  73. IceCube-251130A: Upper limits from a search for additional neutrino events in IceCube
  74. GRB 251201A: SVOM/GRM observation of a burst
  75. GRB 251201B: SVOM/VT optical fading
  76. Swift GRB 251201B : MASTER optical counterpart detection
  77. GRB 251201B: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 1-m telescope at Sutherland Observatory
  78. Swift GRB 251201B: Global MASTER-Net observations report
  79. GRB 251201B: Enhanced Swift-XRT position
  80. EP251118a: Mondy, CrAO, Assy and SAO RAS/Zeiss-1000 optical observations
  81. GRB 251201B: Swift detection of a burst with an optical counterpart
  82. GRB 251201B: Fermi GBM Final Real-time Localization
  83. EP251130a: Mondy optical observations
  84. EP251130a: Optical detections with Kinder observations
  85. SVOM GRB251201.19: Global MASTER-Net observations report
  86. EP251130a: SAO RAS optical observations
  87. EP251130a: GTC OSIRIS+ redshift z = 4.035 and rebrightening
  88. EP251130A: Optical observation from 1.3m DFOT
  89. EP251130a: refined analysis of the EP-WXT and EP-FXT observations
  90. EP251130a: JinShan optical observations
  91. GRB 251201A: MAXI/GSC detection
  92. Fermi GRB 251130B: Global MASTER-Net observations report
  93. GRB 251127A: SVOM/GRM observation
  94. IceCube Alert 251130.75: Global MASTER-Net observations report
  95. EP251130a: Swift-XRT counterpart detection
  96. EP251130a: Global MASTER-Net observations report
  97. EP251130a: COLIBRÍ optical counterpart candidate
  98. EP251130a: Einstein Probe detection of an X-ray transient
  99. GRB 251129A / EP251129a: SAO RAS optical observations
  100. GRB 251126A: SAO RAS optical observations

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