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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"

28097 results found.

  1. EP251130a: Mondy and AbAO optical observations
  2. GRB 251208A: AstroSat CZTI detection
  3. Fermi GBM Sub-Threshold Detection of GRB 251205A
  4. GRB 251208A: Glowbug gamma-ray detection
  5. GRB 251208B: COLIBRÍ optical upper limits
  6. EP251118a / GRB 251118C: VLT/MUSE redshift confirmation
  7. Fermi GRB 251209A: Global MASTER-Net observations report
  8. Fermi GRB 251208C: Global MASTER-Net observations report
  9. GRB 251206A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  10. GRB 251208B: Swift-XRT afterglow detection
  11. GRB 251208D: LAST optical upper limit
  12. GRB 251208D: LCO analysis of the XRT sources
  13. GRB 251208B: Fermi GBM Observation
  14. GRB 251208B: GROWTH-India Telescope optical upper limits
  15. GRB 251205A: J-band detection with WINTER
  16. GRB 251208D: Swift-XRT observations
  17. GRB 251208A: SVOM/GRM observation of a short burst
  18. GRB 251208C: SVOM/GRM observation of a short burst
  19. GRB 251129A: e-MERLIN C-band observations
  20. LAT GRB251208.43: Global MASTER-Net observations report
  21. GRB 251205A: Liverpool Telescope further optical follow-up observations
  22. GRB 251208D: LCO optical upper limits
  23. SVOM GRB251208D: Global MASTER-Net observations report
  24. GRB 251208B: Fermi-LAT detection
  25. GRB 251208B: Swift/BAT-GUANO arcminute localization of a burst
  26. GRB 251208D: SVOM possible detection of a faint burst
  27. GRB 251205A : MITSuME Akeno optical afterglow candidate detection
  28. GRB 251205A: Liverpool Telescope further optical follow-up observations
  29. SVOM GRB251206.86: Global MASTER-Net observations report
  30. GRB 251205A: GROWTH-India Telescope optical observations
  31. GRB 251205A: Swift-BAT refined analysis
  32. GRB 251205A: Swift-XRT refined Analysis
  33. GRB 251205A: Swift/UVOT Detection
  34. GRB 251205A: Liverpool Telescope optical follow-up observations
  35. GRB 251203C: Swift/UVOT Upper Limit
  36. GRB 251205A: COLIBRÍ optical observations
  37. GRB 251205A: NOT optical observations
  38. GRB 251205A: Enhanced Swift-XRT position
  39. Swift GRB 251205A : MASTER OT detection with host galaxy
  40. GRB 251205A: Swift detection of a burst with an optical afterglow
  41. Swift GRB251205A: Global MASTER-Net observations report
  42. SVOM/sb25120502: SVOM detection of a faint X-ray transient candidate
  43. GRB 251202A / EP251202a: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 40-cm and 1-m telescopes at McDonald Observatory
  44. GRB 251203C: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  45. GRB 251202A: SVOM/GRM observation
  46. GRB 251203A: GECAM-B observation of a burst
  47. GRB 251203A: SVOM/GRM observation
  48. GRB 251203C: J-band observations with WINTER
  49. GRB 251129B: Glowbug gamma-ray detection of a short burst
  50. GRB 251203A: AstroSat CZTI detection
  51. GRB 251203C: SVOM/VT optical counterpart
  52. GRB 251203C: EP-FXT follow-up observation
  53. GRB 251203B: Swift-XRT observations
  54. GRB 251203C: LCO optical upper limits
  55. GRB 251203B: LCO optical upper limits
  56. GRB 251203B: SVOM/VT optical observation
  57. GRB 251202A / EP251202a: Liverpool Telescope optical follow-up observations
  58. SVOM GRB251203.77: Global MASTER-Net observations report
  59. SVOM GRB251203B: Global MASTER-Net observations report
  60. GRB 251203B: SVOM detection of a burst
  61. EP251130a: MAO/AZT-22 optical observations
  62. GRB 251201B: Fermi GBM Observation
  63. EP251202a/GRB 251202A: KAIT optical observations
  64. EP251130a: ULL-ASTRO-MASTER late detection of the optical afterglow with LCO 1-m telescope at Teide Observatory
  65. Fermi GRB 251202B: Global MASTER-Net observations report
  66. IPN triangulation of GRB 251129B (short/hard)
  67. GRB251129A/EP251129a: Swift UVOT detection
  68. GRB 251202A: Fermi GBM Observation
  69. GRB 251202A: Swift/UVOT Detection
  70. GRB 251201B: Kilonova-Catcher optical afterglow detection
  71. GRB 251201B: Swift/UVOT Detection
  72. GRB 251130B: Glowbug gamma-ray detection
  73. EP251130a: continued NOT optical observations indicate steep fading phase
  74. Fermi-LAT Gamma-ray Observations of IceCube-251130A
  75. EP251202a/GRB 251202A: refined analysis of the EP-WXT observations
  76. GRB 251126A: SAO RAS optical marginal detection
  77. GRB 251202A: Swift-XRT afterglow detection
  78. EP251129a/GRB 251129A: NOWT Detection
  79. GRB 251126A: SVOM/VT optical observation
  80. EP251130a: SVOM/VT optical observation
  81. Fermi GRB 251202A: Global MASTER-Net observations report
  82. EP251202a/GRB 251202A: Einstein Probe detection of an X-ray transient
  83. GRB 251201B: Swift-XRT refined Analysis
  84. IceCube-251130A: Upper limits from a search for additional neutrino events in IceCube
  85. GRB 251201A: SVOM/GRM observation of a burst
  86. GRB 251201B: SVOM/VT optical fading
  87. Swift GRB 251201B : MASTER optical counterpart detection
  88. GRB 251201B: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 1-m telescope at Sutherland Observatory
  89. Swift GRB 251201B: Global MASTER-Net observations report
  90. GRB 251201B: Enhanced Swift-XRT position
  91. EP251118a: Mondy, CrAO, Assy and SAO RAS/Zeiss-1000 optical observations
  92. GRB 251201B: Swift detection of a burst with an optical counterpart
  93. GRB 251201B: Fermi GBM Final Real-time Localization
  94. EP251130a: Mondy optical observations
  95. EP251130a: Optical detections with Kinder observations
  96. SVOM GRB251201.19: Global MASTER-Net observations report
  97. EP251130a: SAO RAS optical observations
  98. EP251130a: GTC OSIRIS+ redshift z = 4.035 and rebrightening
  99. EP251130A: Optical observation from 1.3m DFOT
  100. EP251130a: refined analysis of the EP-WXT and EP-FXT observations

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