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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"

28221 results found.

  1. EP-WXT trigger 01709249380: confirmation of a stellar flare by BOOTES-5
  2. GRB 251205A: ZTF and ATLAS optical afterglow detections
  3. GRB 251205A: GROWTH-India Telescope optical observations
  4. GRB 251205A: Swift-XRT refined Analysis
  5. GRB 251205A: Swift/UVOT Detection
  6. Konus-Wind detection of GRB 251118A
  7. GRB 251205A: Zeiss-1000 Koshka observatory optical observations
  8. GRB 251205A: GOTO optical afterglow detection
  9. GRB 251205A: NOT optical observations
  10. GRB 251205A: GTC/OSIRIS+ redshift z = 1.100
  11. GRB 251205A: Enhanced Swift-XRT position
  12. Swift GRB 251205A : MASTER OT detection with host galaxy
  13. GRB 251205A: Swift detection of a burst with an optical afterglow
  14. GRB 251126B: Fermi GBM Final Localization
  15. GRB 251203A: Insight-HXMT/HE detection
  16. SVOM/sb25120502: SVOM detection of a faint X-ray transient candidate
  17. GRB 251202A / EP251202a: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 40-cm and 1-m telescopes at McDonald Observatory
  18. GRB 251202A: SVOM/GRM observation
  19. GRB 251201B: SALT spectroscopic redshift z = 1.599
  20. GRB 251129B: Glowbug gamma-ray detection of a short burst
  21. GRB 251203A: AstroSat CZTI detection
  22. GRB 251203C: LCO optical afterglow confirmation
  23. GRB 251203C: SVOM/VT optical counterpart
  24. GRB 251129A/EP251129a : SVOM/ECLAIRs refined analysis
  25. GRB 251203B: Swift-XRT observations
  26. GRB 251203B: confirmation of a stellar flare by BOOTES-2
  27. GRB 251203B : SVOM trigger sb25120304 is not a GRB
  28. GRB 251203B: LCO optical upper limits
  29. GRB 251202A / EP251202a: Liverpool Telescope optical follow-up observations
  30. GRB 251203C: SVOM detection of a burst
  31. GRB 251203B: SVOM detection of a burst
  32. GRB 251129A / EP251129a: SVOM/VT optical color bluer
  33. GRB 251201B: Insight-HXMT/HE detection
  34. EP251202a / GRB 251202A: Insight-HXMT/HE detection
  35. EP251130a: MAO/AZT-22 optical observations
  36. GRB 251203A: Fermi GBM Final Real-time Localization
  37. EP251202a / GRB251202A: AstroSat CZTI detection
  38. GRB 251201B: Fermi GBM Observation
  39. EP251202a/GRB 251202A: KAIT optical observations
  40. EP251130a: ULL-ASTRO-MASTER late detection of the optical afterglow with LCO 1-m telescope at Teide Observatory
  41. GRB 251202B: Fermi GBM Final Real-time Localization
  42. IPN triangulation of GRB 251129B (short/hard)
  43. GRB251129A/EP251129a: Swift UVOT detection
  44. GRB 251129B: AstroSat CZTI detection
  45. GRB 251202A: Fermi GBM Observation
  46. GRB 251202A: Swift/UVOT Detection
  47. GRB 251201B: Kilonova-Catcher optical afterglow detection
  48. GRB 251201B: Swift/UVOT Detection
  49. GRB 251130B: Glowbug gamma-ray detection
  50. EP251202a / GRB 251202A: LCO r- and i-band optical detection
  51. GRB 251202A: GOTO optical afterglow detection
  52. GRB 251126A: SAO RAS optical marginal detection
  53. GRB 251202A: Swift-XRT afterglow detection
  54. EP251129a/GRB 251129A: NOWT Detection
  55. EP251130a: SVOM/VT optical observation
  56. EP251202a / GRB 251202A: NOT spectroscopic redshift z = 2.785
  57. EP251202a/GRB 251202A: Einstein Probe detection of an X-ray transient
  58. GRB 251201B: Swift-XRT refined Analysis
  59. GRB 251202A: Fermi GBM Final Real-time Localization
  60. GRB 251201B: SVOM/VT optical fading
  61. Swift GRB 251201B : MASTER optical counterpart detection
  62. GRB 251201B: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 1-m telescope at Sutherland Observatory
  63. GRB 251201B: Enhanced Swift-XRT position
  64. GRB 251130B: AstroSat CZTI detection
  65. GRB 251201B: Swift detection of a burst with an optical counterpart
  66. GRB 251201B: Fermi GBM Final Real-time Localization
  67. EP251130a: Mondy optical observations
  68. EP251130a: Optical detections with Kinder observations
  69. EP251130a: SAO RAS optical observations
  70. EP251130a: KAIT optical observations
  71. EP251130A: Optical observation from 1.3m DFOT
  72. GRB 251201A: MAXI/GSC detection
  73. IceCube-251130A - IceCube observation of a high-energy neutrino candidate track-like event
  74. EP251130a: Swift-XRT counterpart detection
  75. GRB 251130B: Fermi GBM Final Localization Correction
  76. GRB 251130B: Fermi GBM Final Real-time Localization
  77. EP251130a: Einstein Probe detection of an X-ray transient
  78. GRB 251130A: Fermi GBM Final Real-time Localization
  79. GRB 251129A / EP251129a: GTC/OSIRIS+ spectroscopic redshift z = 1.460
  80. GRB 251129A / EP251129a: OSN and CAHA optical follow-up
  81. GRB 251128A: AstroSat CZTI detection
  82. GRB 251129A / EP251129a: SAO RAS optical observations
  83. GRB 251126A: SAO RAS optical observations
  84. GRB 251128A: GECAM-B detection
  85. GRB 251128A: Insight-HXMT/HE detection
  86. SVOM GRB 251129A : MASTER optical counterpart detection
  87. GRB 251129A: Swift-XRT afterglow detection
  88. GRB 251129A: Swift ToO observations
  89. EP251129a/GRB 251129A : Einstein Probe detection of an X-ray transient
  90. GRB 251129A: SVOM detection of a burst
  91. GRB 251129A: SVOM detection of a burst
  92. GRB 251126A: TShAO, Mondy, and AbAO optical observations
  93. GRB 251127A: Glowbug gamma-ray detection
  94. GRB 251126A: OHP/T193 optical observations and tentative spectroscopic redshift
  95. GRB 251126A: further SAO RAS optical observations
  96. GRB 250702B: detection of the compact radio counterpart 139 days after the burst
  97. GRB251126A: MAO/AZT-22 optical observations
  98. GRB 251128A: Fermi GBM Final Real-time Localization
  99. GRB251126A: Continued optical observation from 1.3m DFOT
  100. GRB 251126A: Swift/UVOT Detection

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