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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"

32689 results found.

  1. GRB 251129A/EP251129a : SVOM/ECLAIRs refined analysis
  2. GRB 251203B: Swift-XRT observations
  3. GRB 251203B: confirmation of a stellar flare by BOOTES-2
  4. GRB 251203B : SVOM trigger sb25120304 is not a GRB
  5. GRB 251203C: LCO optical upper limits
  6. GRB 251203B: LCO optical upper limits
  7. GRB 251203B: SVOM/VT optical observation
  8. GRB 251202A / EP251202a: Liverpool Telescope optical follow-up observations
  9. GRB 251129A / EP251129a: SVOM/VT optical color bluer
  10. GRB 251201B: Insight-HXMT/HE detection
  11. EP251202a / GRB 251202A: Insight-HXMT/HE detection
  12. EP251130a: MAO/AZT-22 optical observations
  13. EP251202a / GRB251202A: AstroSat CZTI detection
  14. GRB 251202A / EP251202a: SVOM/VT optical observation
  15. GRB 251201B: Fermi GBM Observation
  16. EP251202a/GRB 251202A: KAIT optical observations
  17. EP251130a: ULL-ASTRO-MASTER late detection of the optical afterglow with LCO 1-m telescope at Teide Observatory
  18. Fermi GRB 251202B: Global MASTER-Net observations report
  19. IPN triangulation of GRB 251129B (short/hard)
  20. GRB251129A/EP251129a: Swift UVOT detection
  21. GRB 251202A: Fermi GBM Observation
  22. GRB 251202A: Swift/UVOT Detection
  23. GRB 251201B: Kilonova-Catcher optical afterglow detection
  24. GRB 251201B: Swift/UVOT Detection
  25. GRB 251130B: Glowbug gamma-ray detection
  26. GRB 251201B: GECAM-B observation of a long burst
  27. EP251130a: continued NOT optical observations indicate steep fading phase
  28. GRB 251122A/EP251122a: CrAO ZTSh optical observations
  29. Fermi-LAT Gamma-ray Observations of IceCube-251130A
  30. EP251202a / GRB 251202A: LCO r- and i-band optical detection
  31. GRB 251202A: GOTO optical afterglow detection
  32. EP251202a/GRB 251202A: refined analysis of the EP-WXT observations
  33. GRB 251201A: GECAM-B observation of a burst
  34. GRB 251126A: SAO RAS optical marginal detection
  35. GRB 251202A: Swift-XRT afterglow detection
  36. EP251129a/GRB 251129A: NOWT Detection
  37. GRB 251126A: SVOM/VT optical observation
  38. EP251130a: SVOM/VT optical observation
  39. EP251202a / GRB 251202A: NOT spectroscopic redshift z = 2.785
  40. Fermi GRB 251202A: Global MASTER-Net observations report
  41. EP251202a/GRB 251202A: Einstein Probe detection of an X-ray transient
  42. IceCube-251130A: Upper limits from a search for additional neutrino events in IceCube
  43. GRB 251201A: SVOM/GRM observation of a burst
  44. GRB 251201B: SVOM/VT optical fading
  45. Swift GRB 251201B : MASTER optical counterpart detection
  46. GRB 251201B: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 1-m telescope at Sutherland Observatory
  47. Swift GRB 251201B: Global MASTER-Net observations report
  48. EP251118a: Mondy, CrAO, Assy and SAO RAS/Zeiss-1000 optical observations
  49. GRB 251130B: AstroSat CZTI detection
  50. EP251130a: Mondy optical observations
  51. EP251130a: Optical detections with Kinder observations
  52. EP251130a: SAO RAS optical observations
  53. EP251130a: GTC OSIRIS+ redshift z = 4.035 and rebrightening
  54. EP251130a: KAIT optical observations
  55. EP251130A: Optical observation from 1.3m DFOT
  56. EP251130a: refined analysis of the EP-WXT and EP-FXT observations
  57. EP251130a: JinShan optical observations
  58. Fermi GRB 251130B: Global MASTER-Net observations report
  59. GRB 251127A: SVOM/GRM observation
  60. EP251130a: Swift-XRT counterpart detection
  61. EP251130a: Global MASTER-Net observations report
  62. EP251130a: COLIBRÍ optical counterpart candidate
  63. EP251129a/GRB 251129A: EP-FXT follow-up observations
  64. GRB 251129A / EP251129a: GTC/OSIRIS+ spectroscopic redshift z = 1.460
  65. GRB 251128A: AstroSat CZTI detection
  66. GRB 251129A / EP251129a: SAO RAS optical observations
  67. GRB 251126A: SAO RAS optical observations
  68. GRB 251128A: GECAM-B detection
  69. GRB 251128A: SVOM/GRM observation of a long burst
  70. GRB 251128A: Insight-HXMT/HE detection
  71. SVOM GRB 251129A : MASTER optical counterpart detection
  72. GRB 251129A: Swift-XRT afterglow detection
  73. GRB 251129A: Swift ToO observations
  74. GRB 251129A / EP251129a: SVOM/VT optical fading
  75. EP251129a: Global MASTER-Net observations report
  76. GRB 251129A: Optical Observations via Virtual Telescope Project, Italy
  77. EP251129a/GRB 251129A : Einstein Probe detection of an X-ray transient
  78. GRB 251129A: Correction to the position of the optical counterpar
  79. GRB 251129A: SVOM/VT optical counterpart confirmation with VHF data
  80. GRB 251128A: Fermi GBM Observation
  81. GRB 251129A: SVOM/COLIBRÍ (FM-GFT) optical counterpart candidate
  82. GRB 251126A: Swift-BAT refined analysis
  83. GRB 251126A: TShAO, Mondy, and AbAO optical observations
  84. GRB 251128A: Swift/BAT-GUANO localization skymap of a burst
  85. Fermi GRB 251128A: Global MASTER-Net observations report
  86. GRB 251127A: Glowbug gamma-ray detection
  87. GRB 251126A: OHP/T193 optical observations and tentative spectroscopic redshift
  88. GRB 251126A: further SAO RAS optical observations
  89. GRB 250702B: detection of the compact radio counterpart 139 days after the burst
  90. GRB 251126A NUTTelA-TAO Early Measurements
  91. LIGO/Virgo/KAGRA S251112cm: GECKO/KMTNet tiling observations and transient candidates
  92. GRB251126A: MAO/AZT-22 optical observations
  93. GRB251126A: Continued optical observation from 1.3m DFOT
  94. GRB 251126A: Swift/UVOT Detection
  95. EP251124a: Pan-STARRS ri-band imaging and photometry
  96. GRB 251126A: Mondy and SAO RAS optical observations
  97. GRB 251126A : MITSuME Akeno optical afterglow candidate detection
  98. GRB 251126A: NOT optical observations
  99. GRB 251126A: 1.3m DFOT optical afterglow detection
  100. GRB 251126A: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 1-m telescope at McDonald Observatory

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