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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"

18488 results found.

  1. GRB 251213A: AstroSat CZTI detection
  2. GRB 251214B: Swift/UVOT Detection
  3. GRB 251214B: COLIBRÍ observations of the afterglow
  4. EP251214a: EP-FXT non-detection and upper limit
  5. GRB 251214B: 1.3m DFOT optical detection
  6. GRB 251214B: Enhanced Swift-XRT position
  7. GRB 251214B: Xinglong-2.16m optical observation
  8. GRB 251214B: SVOM/C-GFT optical observations
  9. EP251214a: COLIBRÍ optical upper limit
  10. EP251214.305: COLIBRÍ optical upper limit
  11. GRB 251214B: Swift detection of a burst with an optical counterpart
  12. EP251214a: EP-WXT detection of an X-ray transient possibly associated with GRB 251214A
  13. EP251212a: KAIT optical upper limit
  14. EP251212a / GRB 251212A: AstroSat CZTI detection
  15. EP251212a: EP-FXT follow-up observation
  16. EP251212a : COLIBRÍ optical upper limit
  17. EP251212a: Einstein Probe detection of an X-ray transient
  18. IceCube-251210A: DDOTI Optical Upper Limit
  19. GRB 251209A: Fermi GBM observation
  20. GRB 251205A: 1.3m DFOT optical upper limit
  21. EP251124a: Mondy optical upper limit
  22. GRB 251129A/EP251129a: AbAO and Mondy optical observations
  23. EP251130a: Mondy and AbAO optical observations
  24. GRB 251208B: COLIBRÍ optical upper limits
  25. EP251118a / GRB 251118C: VLT/MUSE redshift confirmation
  26. GRB 251206A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  27. GRB 251208B: Swift-XRT afterglow detection
  28. GRB 251208D: LAST optical upper limit
  29. GRB 251209A: Fermi GBM Final Real-time Localization
  30. GRB 251208D: LCO analysis of the XRT sources
  31. GRB 251208B: GROWTH-India Telescope optical upper limits
  32. GRB 251205A: J-band detection with WINTER
  33. GRB 251208A: SVOM/GRM observation of a short burst
  34. GRB 251208C: SVOM/GRM observation of a short burst
  35. GRB 251205A: Liverpool Telescope further optical follow-up observations
  36. GRB 251208D: LCO optical upper limits
  37. GRB 251205A : MITSuME Akeno optical afterglow candidate detection
  38. GRB 251205A: Liverpool Telescope further optical follow-up observations
  39. EP-WXT trigger 01709249380: confirmation of a stellar flare by BOOTES-5
  40. The EP-WXT trigger 01709249380 is likely a flaring star
  41. GRB 251205A: GROWTH-India Telescope optical observations
  42. GRB 251205A: Swift-BAT refined analysis
  43. GRB 251205A: Swift-XRT refined Analysis
  44. GRB 251205A: Swift/UVOT Detection
  45. GRB 251205A: Liverpool Telescope optical follow-up observations
  46. GRB 251203C: Swift/UVOT Upper Limit
  47. GRB 251205A: COLIBRÍ optical observations
  48. GRB 251205A: NOT optical observations
  49. GRB 251205A: Enhanced Swift-XRT position
  50. Swift GRB 251205A : MASTER OT detection with host galaxy
  51. GRB 251205A: Swift detection of a burst with an optical afterglow
  52. GRB 251202A / EP251202a: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 40-cm and 1-m telescopes at McDonald Observatory
  53. GRB 251203C: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  54. GRB 251202A: SVOM/GRM observation
  55. GRB 251203A: SVOM/GRM observation
  56. GRB 251203C: J-band observations with WINTER
  57. GRB 251203C: SVOM/VT optical counterpart
  58. GRB 251203C: EP-FXT follow-up observation
  59. GRB 251129A/EP251129a : SVOM/ECLAIRs refined analysis
  60. GRB 251203C: LCO optical upper limits
  61. GRB 251203B: LCO optical upper limits
  62. GRB 251203B: SVOM/VT optical observation
  63. GRB 251202A / EP251202a: Liverpool Telescope optical follow-up observations
  64. GRB 251203B: SVOM detection of a burst
  65. EP251130a: MAO/AZT-22 optical observations
  66. EP251202a/GRB 251202A: KAIT optical observations
  67. EP251130a: ULL-ASTRO-MASTER late detection of the optical afterglow with LCO 1-m telescope at Teide Observatory
  68. IPN triangulation of GRB 251129B (short/hard)
  69. GRB251129A/EP251129a: Swift UVOT detection
  70. GRB 251202A: Swift/UVOT Detection
  71. GRB 251201B: Kilonova-Catcher optical afterglow detection
  72. GRB 251201B: Swift/UVOT Detection
  73. EP251202a/GRB 251202A: refined analysis of the EP-WXT observations
  74. GRB 251126A: SAO RAS optical marginal detection
  75. GRB 251202A: Swift-XRT afterglow detection
  76. EP251129a/GRB 251129A: NOWT Detection
  77. GRB 251126A: SVOM/VT optical observation
  78. EP251130a: SVOM/VT optical observation
  79. EP251202a/GRB 251202A: Einstein Probe detection of an X-ray transient
  80. GRB 251201A: SVOM/GRM observation of a burst
  81. GRB 251201B: SVOM/VT optical fading
  82. GRB 251201B: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 1-m telescope at Sutherland Observatory
  83. GRB 251201B: Enhanced Swift-XRT position
  84. EP251118a: Mondy, CrAO, Assy and SAO RAS/Zeiss-1000 optical observations
  85. GRB 251201B: Swift detection of a burst with an optical counterpart
  86. EP251130a: Mondy optical observations
  87. EP251130a: Optical detections with Kinder observations
  88. EP251130a: SAO RAS optical observations
  89. EP251130A: Optical observation from 1.3m DFOT
  90. EP251130a: refined analysis of the EP-WXT and EP-FXT observations
  91. EP251130a: JinShan optical observations
  92. GRB 251127A: SVOM/GRM observation
  93. EP251130a: COLIBRÍ optical counterpart candidate
  94. EP251130a: Einstein Probe detection of an X-ray transient
  95. EP251129a/GRB 251129A: EP-FXT follow-up observations
  96. GRB 251129A / EP251129a: SAO RAS optical observations
  97. GRB 251126A: SAO RAS optical observations
  98. GRB 251128A: SVOM/GRM observation of a long burst
  99. SVOM GRB 251129A : MASTER optical counterpart detection
  100. GRB 251129A: Swift-XRT afterglow detection

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