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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').
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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"

18480 results found.

  1. EP251214a: COLIBRÍ optical upper limit
  2. EP251214.305: COLIBRÍ optical upper limit
  3. GRB 251214B: Swift detection of a burst with an optical counterpart
  4. EP251214a: EP-WXT detection of an X-ray transient possibly associated with GRB 251214A
  5. EP251212a: KAIT optical upper limit
  6. EP251212a / GRB 251212A: AstroSat CZTI detection
  7. EP251212a: EP-FXT follow-up observation
  8. EP251212a : COLIBRÍ optical upper limit
  9. EP251212a: Einstein Probe detection of an X-ray transient
  10. IceCube-251210A: DDOTI Optical Upper Limit
  11. GRB 251209A: Fermi GBM observation
  12. GRB 251205A: 1.3m DFOT optical upper limit
  13. EP251124a: Mondy optical upper limit
  14. GRB 251129A/EP251129a: AbAO and Mondy optical observations
  15. EP251130a: Mondy and AbAO optical observations
  16. GRB 251208B: COLIBRÍ optical upper limits
  17. EP251118a / GRB 251118C: VLT/MUSE redshift confirmation
  18. GRB 251206A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  19. GRB 251208B: Swift-XRT afterglow detection
  20. GRB 251208D: LAST optical upper limit
  21. GRB 251209A: Fermi GBM Final Real-time Localization
  22. GRB 251208D: LCO analysis of the XRT sources
  23. GRB 251208B: GROWTH-India Telescope optical upper limits
  24. GRB 251205A: J-band detection with WINTER
  25. GRB 251208A: SVOM/GRM observation of a short burst
  26. GRB 251208C: SVOM/GRM observation of a short burst
  27. GRB 251205A: Liverpool Telescope further optical follow-up observations
  28. GRB 251208D: LCO optical upper limits
  29. GRB 251205A : MITSuME Akeno optical afterglow candidate detection
  30. GRB 251205A: Liverpool Telescope further optical follow-up observations
  31. EP-WXT trigger 01709249380: confirmation of a stellar flare by BOOTES-5
  32. The EP-WXT trigger 01709249380 is likely a flaring star
  33. GRB 251205A: GROWTH-India Telescope optical observations
  34. GRB 251205A: Swift-BAT refined analysis
  35. GRB 251205A: Swift-XRT refined Analysis
  36. GRB 251205A: Swift/UVOT Detection
  37. GRB 251205A: Liverpool Telescope optical follow-up observations
  38. GRB 251203C: Swift/UVOT Upper Limit
  39. GRB 251205A: COLIBRÍ optical observations
  40. GRB 251205A: NOT optical observations
  41. GRB 251205A: Enhanced Swift-XRT position
  42. Swift GRB 251205A : MASTER OT detection with host galaxy
  43. GRB 251205A: Swift detection of a burst with an optical afterglow
  44. GRB 251202A / EP251202a: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 40-cm and 1-m telescopes at McDonald Observatory
  45. GRB 251203C: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  46. GRB 251202A: SVOM/GRM observation
  47. GRB 251203A: SVOM/GRM observation
  48. GRB 251203C: J-band observations with WINTER
  49. GRB 251203C: SVOM/VT optical counterpart
  50. GRB 251203C: EP-FXT follow-up observation
  51. GRB 251129A/EP251129a : SVOM/ECLAIRs refined analysis
  52. GRB 251203C: LCO optical upper limits
  53. GRB 251203B: LCO optical upper limits
  54. GRB 251203B: SVOM/VT optical observation
  55. GRB 251202A / EP251202a: Liverpool Telescope optical follow-up observations
  56. GRB 251203B: SVOM detection of a burst
  57. EP251130a: MAO/AZT-22 optical observations
  58. EP251202a/GRB 251202A: KAIT optical observations
  59. EP251130a: ULL-ASTRO-MASTER late detection of the optical afterglow with LCO 1-m telescope at Teide Observatory
  60. IPN triangulation of GRB 251129B (short/hard)
  61. GRB251129A/EP251129a: Swift UVOT detection
  62. GRB 251202A: Swift/UVOT Detection
  63. GRB 251201B: Kilonova-Catcher optical afterglow detection
  64. GRB 251201B: Swift/UVOT Detection
  65. EP251202a/GRB 251202A: refined analysis of the EP-WXT observations
  66. GRB 251126A: SAO RAS optical marginal detection
  67. GRB 251202A: Swift-XRT afterglow detection
  68. EP251129a/GRB 251129A: NOWT Detection
  69. GRB 251126A: SVOM/VT optical observation
  70. EP251130a: SVOM/VT optical observation
  71. EP251202a/GRB 251202A: Einstein Probe detection of an X-ray transient
  72. GRB 251201A: SVOM/GRM observation of a burst
  73. GRB 251201B: SVOM/VT optical fading
  74. GRB 251201B: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 1-m telescope at Sutherland Observatory
  75. GRB 251201B: Enhanced Swift-XRT position
  76. EP251118a: Mondy, CrAO, Assy and SAO RAS/Zeiss-1000 optical observations
  77. GRB 251201B: Swift detection of a burst with an optical counterpart
  78. EP251130a: Mondy optical observations
  79. EP251130a: Optical detections with Kinder observations
  80. EP251130a: SAO RAS optical observations
  81. EP251130A: Optical observation from 1.3m DFOT
  82. EP251130a: refined analysis of the EP-WXT and EP-FXT observations
  83. EP251130a: JinShan optical observations
  84. GRB 251127A: SVOM/GRM observation
  85. EP251130a: COLIBRÍ optical counterpart candidate
  86. EP251130a: Einstein Probe detection of an X-ray transient
  87. EP251129a/GRB 251129A: EP-FXT follow-up observations
  88. GRB 251129A / EP251129a: SAO RAS optical observations
  89. GRB 251126A: SAO RAS optical observations
  90. GRB 251128A: SVOM/GRM observation of a long burst
  91. SVOM GRB 251129A : MASTER optical counterpart detection
  92. GRB 251129A: Swift-XRT afterglow detection
  93. The EP-WXT trigger 01709248941 is triggered by the known source Perseus Cluster
  94. EP251129a/GRB 251129A : Einstein Probe detection of an X-ray transient
  95. GRB 251129A: SVOM/COLIBRÍ (FM-GFT) optical counterpart candidate
  96. GRB 251129A: SVOM detection of a burst
  97. SVOM GRB251129A: Global MASTER-Net observations report
  98. GRB 251129A: SVOM detection of a burst
  99. GRB 251126A: TShAO, Mondy, and AbAO optical observations
  100. GRB 251128A: Swift/BAT-GUANO localization skymap of a burst

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