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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"

41870 results found.

  1. GRB 251205A: Swift/UVOT Detection
  2. GRB 251205A: Liverpool Telescope optical follow-up observations
  3. GRB 251203C: Swift/UVOT Upper Limit
  4. Konus-Wind detection of GRB 251118A
  5. GRB 251205A: Zeiss-1000 Koshka observatory optical observations
  6. GRB 251205A: COLIBRÍ optical observations
  7. GRB 251205A: GOTO optical afterglow detection
  8. GRB 251205A: NOT optical observations
  9. GRB 251205A: GTC/OSIRIS+ redshift z = 1.100
  10. GRB 251205A: Enhanced Swift-XRT position
  11. Swift GRB 251205A : MASTER OT detection with host galaxy
  12. GRB 251205A: Swift detection of a burst with an optical afterglow
  13. Swift GRB251205A: Global MASTER-Net observations report
  14. GRB 251126B: Fermi GBM Final Localization
  15. GRB 251203A: Insight-HXMT/HE detection
  16. GRB 251203C: SVOM/ECLAIRs refined analysis
  17. SVOM/sb25120502: SVOM detection of a faint X-ray transient candidate
  18. GRB 251202A / EP251202a: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 40-cm and 1-m telescopes at McDonald Observatory
  19. GRB 251203C: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  20. GRB 251202A: SVOM/GRM observation
  21. GRB 251203A: GECAM-B observation of a burst
  22. GRB 251203A: SVOM/GRM observation
  23. GRB 251201B: SALT spectroscopic redshift z = 1.599
  24. GRB 251203C: J-band observations with WINTER
  25. GRB 251129B: Glowbug gamma-ray detection of a short burst
  26. GRB 251203A: AstroSat CZTI detection
  27. EP251130a: JinShan near-infrared observations
  28. GRB 251203C: SVOM/VT optical counterpart
  29. GRB 251203C: EP-FXT follow-up observation
  30. GRB 251129A/EP251129a : SVOM/ECLAIRs refined analysis
  31. GRB 251129B: GECAM-B observation of a burst
  32. GRB 251203B: Swift-XRT observations
  33. GRB 251203B: confirmation of a stellar flare by BOOTES-2
  34. GRB 251203B : SVOM trigger sb25120304 is not a GRB
  35. GRB 251203C: LCO optical upper limits
  36. GRB 251203B: LCO optical upper limits
  37. GRB 251203B: SVOM/VT optical observation
  38. GRB 251202A / EP251202a: Liverpool Telescope optical follow-up observations
  39. GRB 251203C: SVOM detection of a burst
  40. SVOM GRB251203.77: Global MASTER-Net observations report
  41. SVOM GRB251203B: Global MASTER-Net observations report
  42. GRB 251203B: SVOM detection of a burst
  43. GRB 251129A / EP251129a: SVOM/VT optical color bluer
  44. GRB 251201B: Insight-HXMT/HE detection
  45. EP251202a / GRB 251202A: Insight-HXMT/HE detection
  46. EP251130a: MAO/AZT-22 optical observations
  47. GRB 251203A: Fermi GBM Final Real-time Localization
  48. EP251202a / GRB251202A: AstroSat CZTI detection
  49. GRB 251202A / EP251202a: SVOM/VT optical observation
  50. GRB 251201B: Fermi GBM Observation
  51. EP251202a/GRB 251202A: KAIT optical observations
  52. EP251130a: ULL-ASTRO-MASTER late detection of the optical afterglow with LCO 1-m telescope at Teide Observatory
  53. Fermi GRB 251202B: Global MASTER-Net observations report
  54. GRB 251202B: Fermi GBM Final Real-time Localization
  55. GRB251129A/EP251129a: Swift UVOT detection
  56. GRB 251129B: AstroSat CZTI 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. GRB 251201B: GECAM-B observation of a long burst
  63. EP251130a: continued NOT optical observations indicate steep fading phase
  64. GRB 251122A/EP251122a: CrAO ZTSh optical observations
  65. Fermi-LAT Gamma-ray Observations of IceCube-251130A
  66. EP251202a / GRB 251202A: LCO r- and i-band optical detection
  67. GRB 251202A: GOTO optical afterglow detection
  68. EP251202a/GRB 251202A: refined analysis of the EP-WXT observations
  69. GRB 251201A: GECAM-B observation of a burst
  70. GRB 251126A: SAO RAS optical marginal detection
  71. GRB 251202A: Swift-XRT afterglow detection
  72. EP251129a/GRB 251129A: NOWT Detection
  73. GRB 251126A: SVOM/VT optical observation
  74. EP251130a: SVOM/VT optical observation
  75. EP251202a / GRB 251202A: NOT spectroscopic redshift z = 2.785
  76. Fermi GRB 251202A: Global MASTER-Net observations report
  77. EP251202a/GRB 251202A: Einstein Probe detection of an X-ray transient
  78. GRB 251201B: Swift-XRT refined Analysis
  79. IceCube-251130A: Upper limits from a search for additional neutrino events in IceCube
  80. EP251202a/trigger 01709249064: Las Cumbres discovery of the optical counterpart
  81. GRB 251202A: Fermi GBM Final Real-time Localization
  82. GRB 251201A: SVOM/GRM observation of a burst
  83. GRB 251201B: SVOM/VT optical fading
  84. Swift GRB 251201B : MASTER optical counterpart detection
  85. GRB 251201B: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 1-m telescope at Sutherland Observatory
  86. Swift GRB 251201B: Global MASTER-Net observations report
  87. GRB 251201B: Enhanced Swift-XRT position
  88. EP251118a: Mondy, CrAO, Assy and SAO RAS/Zeiss-1000 optical observations
  89. GRB 251130B: AstroSat CZTI detection
  90. GRB 251201B: Swift detection of a burst with an optical counterpart
  91. GRB 251201B: Fermi GBM Final Real-time Localization
  92. EP251130a: Mondy optical observations
  93. EP251130a: Optical detections with Kinder observations
  94. SVOM GRB251201.19: Global MASTER-Net observations report
  95. EP251130a: SAO RAS optical observations
  96. EP251130a: GTC OSIRIS+ redshift z = 4.035 and rebrightening
  97. EP251130a: KAIT optical observations
  98. EP251130A: Optical observation from 1.3m DFOT
  99. EP251130a: refined analysis of the EP-WXT and EP-FXT observations
  100. EP251130a: JinShan optical observations

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