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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"

15359 results found.

  1. GRB 251214D: GECAM-B observation of a long burst
  2. GRB 251214B: Fermi GBM Observation
  3. GRB 251209A: Insight-HXMT/HE detection
  4. GRB 251215A: Swift ToO observations
  5. GRID detection of GRB 251213A
  6. GRB 251203B: AbAO optical observations
  7. GRB 251215A: Swift/BAT-GUANO arcminute localization of a burst
  8. GRB 251214B: GECAM-B observation of a long burst
  9. GRB 251213A: SVOM/GRM observation
  10. EP251214a: KAIT optical upper limit
  11. GRB 251214D: AstroSat CZTI detection of a long burst
  12. GRB 251213A: AstroSat CZTI detection
  13. GRB 251214A: AstroSat CZTI detection
  14. GRB 251213A: GECAM-B detection
  15. GRB 251214A: GECAM-B observation of a likely long burst
  16. EP251214a: COLIBRÍ optical upper limit
  17. EP251214a: EP-WXT detection of an X-ray transient possibly associated with GRB 251214A
  18. EP251212a: KAIT optical upper limit
  19. EP251212a / GRB 251212A: AstroSat CZTI detection
  20. GRB 251211B: AstroSat CZTI detection
  21. IceCube-251210A: No Candidate Transients from the Zwicky Transient Facility
  22. Fermi-LAT Gamma-ray Observations of IceCube-251210A
  23. IceCube-251210A: Upper limits from a search for additional neutrino events in IceCube
  24. IceCube-251210A: DDOTI Optical Upper Limit
  25. GRB 251209A: Fermi GBM observation
  26. GRB 251209A: AstroSat CZTI detection
  27. IceCube-251210A - IceCube observation of a high-energy neutrino candidate track-like event
  28. EP251124a: Mondy optical upper limit
  29. GRB 251208A: AstroSat CZTI detection
  30. EP251118a / GRB 251118C: VLT/MUSE redshift confirmation
  31. GRB 251208C: GECAM-B observation of a short burst
  32. GRB 251208A: GECAM-B observation of a short burst
  33. GRB 251208D: LAST optical upper limit
  34. GRB 251208D: LCO analysis of the XRT sources
  35. GRB 251208B: Fermi GBM Observation
  36. GRB 251208A: SVOM/GRM observation of a short burst
  37. GRB 251208C: SVOM/GRM observation of a short burst
  38. GRB 251205A: Liverpool Telescope further optical follow-up observations
  39. GRB 251208B: Swift ToO observations
  40. GRB 251208B: Fermi-LAT detection
  41. GRB 251208B: Swift/BAT-GUANO arcminute localization of a burst
  42. GRB 251208D: SVOM possible detection of a faint burst
  43. GRB 251206A: SVOM detection of a burst through offline search
  44. GRB 251205A : MITSuME Akeno optical afterglow candidate detection
  45. GRB 251205A: FTW optical and NIR observations
  46. EP-WXT trigger 01709249380: KAIT confirmation of a stellar flare
  47. GRB 251205A: Liverpool Telescope further optical follow-up observations
  48. EP-WXT trigger 01709249380: confirmation of a stellar flare by BOOTES-5
  49. GRB 251205A: ZTF and ATLAS optical afterglow detections
  50. GRB 251205A: GROWTH-India Telescope optical observations
  51. GRB 251205A: Liverpool Telescope optical follow-up observations
  52. GRB 251203C: Swift/UVOT Upper Limit
  53. Konus-Wind detection of GRB 251118A
  54. GRB 251203A: Insight-HXMT/HE detection
  55. GRB 251203C: SVOM/ECLAIRs refined analysis
  56. SVOM/sb25120502: SVOM detection of a faint X-ray transient candidate
  57. GRB 251202A / EP251202a: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 40-cm and 1-m telescopes at McDonald Observatory
  58. GRB 251203C: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  59. GRB 251202A: SVOM/GRM observation
  60. GRB 251203A: GECAM-B observation of a burst
  61. GRB 251203A: SVOM/GRM observation
  62. GRB 251203A: AstroSat CZTI detection
  63. EP251130a: JinShan near-infrared observations
  64. GRB 251203C: LCO optical afterglow confirmation
  65. GRB 251129A/EP251129a : SVOM/ECLAIRs refined analysis
  66. GRB 251129B: GECAM-B observation of a burst
  67. GRB 251203B: confirmation of a stellar flare by BOOTES-2
  68. GRB 251202A / EP251202a: Liverpool Telescope optical follow-up observations
  69. GRB 251203C: SVOM detection of a burst
  70. GRB 251203B: SVOM detection of a burst
  71. GRB 251201B: Insight-HXMT/HE detection
  72. EP251202a / GRB 251202A: Insight-HXMT/HE detection
  73. EP251130a: MAO/AZT-22 optical observations
  74. EP251202a / GRB251202A: AstroSat CZTI detection
  75. GRB 251201B: Fermi GBM Observation
  76. EP251130a: ULL-ASTRO-MASTER late detection of the optical afterglow with LCO 1-m telescope at Teide Observatory
  77. GRB 251129B: AstroSat CZTI detection
  78. GRB 251202A: Fermi GBM Observation
  79. GRB 251201B: Kilonova-Catcher optical afterglow detection
  80. GRB 251201B: GECAM-B observation of a long burst
  81. EP251130a: continued NOT optical observations indicate steep fading phase
  82. Fermi-LAT Gamma-ray Observations of IceCube-251130A
  83. GRB 251201A: GECAM-B observation of a burst
  84. GRB 251202A: Swift-XRT afterglow detection
  85. EP251129a/GRB 251129A: NOWT Detection
  86. EP251202a/GRB 251202A: Einstein Probe detection of an X-ray transient
  87. IceCube-251130A: Upper limits from a search for additional neutrino events in IceCube
  88. GRB 251201A: SVOM/GRM observation of a burst
  89. GRB 251130B: AstroSat CZTI detection
  90. EP251130a: SAO RAS optical observations
  91. EP251130a: refined analysis of the EP-WXT and EP-FXT observations
  92. EP251130a: JinShan optical observations
  93. GRB 251127A: SVOM/GRM observation
  94. IceCube-251130A - IceCube observation of a high-energy neutrino candidate track-like event
  95. EP251130a: Swift-XRT counterpart detection
  96. EP251129a/GRB 251129A: EP-FXT follow-up observations
  97. GRB 251129A / EP251129a: GTC/OSIRIS+ spectroscopic redshift z = 1.460
  98. GRB 251129A / EP251129a: OSN and CAHA optical follow-up
  99. GRB 251128A: AstroSat CZTI detection
  100. GRB 251128A: GECAM-B detection

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