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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"

15271 results found.

  1. IceCube-251218A - IceCube observation of a high-energy neutrino candidate track-like event
  2. GRB 251214B: VIRT Optical Upper Limit
  3. GRB 251202A/EP251202a: Koshka optical upper limit
  4. GRB 251214B: Mondy optical upper limit
  5. GRB 251215A: COLIBRÍ optical upper limit
  6. EP251214b: KAIT optical upper limit
  7. GRB 251214B: 1.6m Mephisto observations with newly installed mosaic cameras
  8. GRB 251215A: Glowbug gamma-ray detection
  9. GRB 251214B: UAFO optical upper limit
  10. GRB 251213A: GRID-10B observation
  11. GRB 251214B: AbAO optical observations
  12. GRB 251209A: GECAM-B observation of a long burst
  13. GRB 251214D: GECAM-B observation of a long burst
  14. GRB 251214B: Fermi GBM Observation
  15. GRB 251209A: Insight-HXMT/HE detection
  16. GRB 251215A: Swift ToO observations
  17. GRID detection of GRB 251213A
  18. GRB 251203B: AbAO optical observations
  19. GRB 251215A: Swift/BAT-GUANO arcminute localization of a burst
  20. GRB 251214B: GECAM-B observation of a long burst
  21. GRB 251213A: SVOM/GRM observation
  22. EP251214a: KAIT optical upper limit
  23. GRB 251214D: AstroSat CZTI detection of a long burst
  24. GRB 251213A: AstroSat CZTI detection
  25. GRB 251214A: AstroSat CZTI detection
  26. GRB 251213A: GECAM-B detection
  27. GRB 251214A: GECAM-B observation of a likely long burst
  28. EP251214a: COLIBRÍ optical upper limit
  29. EP251214a: EP-WXT detection of an X-ray transient possibly associated with GRB 251214A
  30. EP251212a: KAIT optical upper limit
  31. EP251212a / GRB 251212A: AstroSat CZTI detection
  32. GRB 251211B: AstroSat CZTI detection
  33. IceCube-251210A: No Candidate Transients from the Zwicky Transient Facility
  34. Fermi-LAT Gamma-ray Observations of IceCube-251210A
  35. IceCube-251210A: Upper limits from a search for additional neutrino events in IceCube
  36. IceCube-251210A: DDOTI Optical Upper Limit
  37. GRB 251209A: Fermi GBM observation
  38. GRB 251209A: AstroSat CZTI detection
  39. IceCube-251210A - IceCube observation of a high-energy neutrino candidate track-like event
  40. EP251124a: Mondy optical upper limit
  41. GRB 251208A: AstroSat CZTI detection
  42. EP251118a / GRB 251118C: VLT/MUSE redshift confirmation
  43. GRB 251208C: GECAM-B observation of a short burst
  44. GRB 251208A: GECAM-B observation of a short burst
  45. GRB 251208D: LAST optical upper limit
  46. GRB 251208D: LCO analysis of the XRT sources
  47. GRB 251208B: Fermi GBM Observation
  48. GRB 251208A: SVOM/GRM observation of a short burst
  49. GRB 251208C: SVOM/GRM observation of a short burst
  50. GRB 251205A: Liverpool Telescope further optical follow-up observations
  51. GRB 251208B: Swift ToO observations
  52. GRB 251208B: Fermi-LAT detection
  53. GRB 251208B: Swift/BAT-GUANO arcminute localization of a burst
  54. GRB 251208D: SVOM possible detection of a faint burst
  55. GRB 251206A: SVOM detection of a burst through offline search
  56. GRB 251205A : MITSuME Akeno optical afterglow candidate detection
  57. GRB 251205A: FTW optical and NIR observations
  58. EP-WXT trigger 01709249380: KAIT confirmation of a stellar flare
  59. GRB 251205A: Liverpool Telescope further optical follow-up observations
  60. EP-WXT trigger 01709249380: confirmation of a stellar flare by BOOTES-5
  61. GRB 251205A: ZTF and ATLAS optical afterglow detections
  62. GRB 251205A: GROWTH-India Telescope optical observations
  63. GRB 251205A: Liverpool Telescope optical follow-up observations
  64. GRB 251203C: Swift/UVOT Upper Limit
  65. Konus-Wind detection of GRB 251118A
  66. GRB 251203A: Insight-HXMT/HE detection
  67. GRB 251203C: SVOM/ECLAIRs refined analysis
  68. SVOM/sb25120502: SVOM detection of a faint X-ray transient candidate
  69. GRB 251202A / EP251202a: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 40-cm and 1-m telescopes at McDonald Observatory
  70. GRB 251203C: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  71. GRB 251202A: SVOM/GRM observation
  72. GRB 251203A: GECAM-B observation of a burst
  73. GRB 251203A: SVOM/GRM observation
  74. GRB 251203A: AstroSat CZTI detection
  75. EP251130a: JinShan near-infrared observations
  76. GRB 251203C: LCO optical afterglow confirmation
  77. GRB 251129A/EP251129a : SVOM/ECLAIRs refined analysis
  78. GRB 251129B: GECAM-B observation of a burst
  79. GRB 251203B: confirmation of a stellar flare by BOOTES-2
  80. GRB 251202A / EP251202a: Liverpool Telescope optical follow-up observations
  81. GRB 251203C: SVOM detection of a burst
  82. GRB 251203B: SVOM detection of a burst
  83. GRB 251201B: Insight-HXMT/HE detection
  84. EP251202a / GRB 251202A: Insight-HXMT/HE detection
  85. EP251130a: MAO/AZT-22 optical observations
  86. EP251202a / GRB251202A: AstroSat CZTI detection
  87. GRB 251201B: Fermi GBM Observation
  88. EP251130a: ULL-ASTRO-MASTER late detection of the optical afterglow with LCO 1-m telescope at Teide Observatory
  89. GRB 251129B: AstroSat CZTI detection
  90. GRB 251202A: Fermi GBM Observation
  91. GRB 251201B: Kilonova-Catcher optical afterglow detection
  92. GRB 251201B: GECAM-B observation of a long burst
  93. EP251130a: continued NOT optical observations indicate steep fading phase
  94. Fermi-LAT Gamma-ray Observations of IceCube-251130A
  95. GRB 251201A: GECAM-B observation of a burst
  96. GRB 251202A: Swift-XRT afterglow detection
  97. EP251129a/GRB 251129A: NOWT Detection
  98. EP251202a/GRB 251202A: Einstein Probe detection of an X-ray transient
  99. IceCube-251130A: Upper limits from a search for additional neutrino events in IceCube
  100. GRB 251201A: SVOM/GRM observation of a burst

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