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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"

12176 results found.

  1. GRB 251206A: SVOM detection of a burst through offline search
  2. GRB 251205A: Swift-XRT refined Analysis
  3. Konus-Wind detection of GRB 251118A
  4. Swift GRB251205A: Global MASTER-Net observations report
  5. GRB 251203A: SVOM/GRM observation
  6. GRB 251203A: AstroSat CZTI detection
  7. GRB 251203C: EP-FXT follow-up observation
  8. GRB 251203B: Swift-XRT observations
  9. GRB 251203B: confirmation of a stellar flare by BOOTES-2
  10. GRB 251203B: SVOM detection of a burst
  11. EP251130a: MAO/AZT-22 optical observations
  12. EP251202a / GRB251202A: AstroSat CZTI detection
  13. Fermi GRB 251202B: Global MASTER-Net observations report
  14. GRB 251129B: AstroSat CZTI detection
  15. GRB 251201B: Swift/UVOT Detection
  16. GRB 251122A/EP251122a: CrAO ZTSh optical observations
  17. Fermi-LAT Gamma-ray Observations of IceCube-251130A
  18. EP251202a/GRB 251202A: refined analysis of the EP-WXT observations
  19. GRB 251202A: Swift-XRT afterglow detection
  20. EP251129a/GRB 251129A: NOWT Detection
  21. GRB 251126A: SVOM/VT optical observation
  22. EP251202a/GRB 251202A: Einstein Probe detection of an X-ray transient
  23. GRB 251201B: Swift-XRT refined Analysis
  24. EP251118a: Mondy, CrAO, Assy and SAO RAS/Zeiss-1000 optical observations
  25. GRB 251130B: AstroSat CZTI detection
  26. EP251130a: Optical detections with Kinder observations
  27. GRB 251201A: MAXI/GSC detection
  28. EP251130a: Swift-XRT counterpart detection
  29. EP251130a: Einstein Probe detection of an X-ray transient
  30. EP251129a/GRB 251129A: EP-FXT follow-up observations
  31. GRB 251128A: AstroSat CZTI detection
  32. GRB 251129A: Swift-XRT afterglow detection
  33. EP251129a: Global MASTER-Net observations report
  34. EP251129a/GRB 251129A : Einstein Probe detection of an X-ray transient
  35. GRB 251126A: TShAO, Mondy, and AbAO optical observations
  36. GRB 251128A: Swift/BAT-GUANO localization skymap of a burst
  37. GRB 251126A: further SAO RAS optical observations
  38. GRB 251126A: Mondy and SAO RAS optical observations
  39. GRB 251126A: Swift-XRT refined Analysis
  40. Fermi GRB 251127A: Global MASTER-Net observations report
  41. Swift GRB 251126A: Global MASTER-Net observations report
  42. GRB 251126A: Swift detection of a burst
  43. GRB 251125B: COLIBRÍ further observations and photometric redshift upper limit of z < 3
  44. Fermi GRB 251125B : MASTER OT J155558.56+581224.1 optical counterpart discovery
  45. Fermi GRB 251125B: Global MASTER-Net observations report
  46. GRB 251125B: Fermi GBM Final Real-time Localization
  47. Fermi GRB 251125A: Global MASTER-Net observations report
  48. EP251124a: Swift-XRT observations
  49. LIGO/Virgo/KAGRA S251112cm: AT 2025adht Kinder follow-up observations
  50. EP251124a: Optical upper limit with Kinder observations
  51. EP251118A: 6 GHz VLA Detection
  52. LIGO/Virgo/KAGRA S251105aj: EP-FXT follow-up observations and preliminary results on SVOM J2320.0-2901
  53. EP251124a: Einstein Probe detection of an X-ray transient
  54. GRB 251122A/EP251122a: Additional, deeper LCO optical r band upper limit
  55. EP251122a / GRB 251122A: optical counterpart candidate with Kinder observations
  56. GRB 251122A / EP251122a: SVOM detection of a long burst
  57. EP251122a: Einstein Probe detection of an X-ray transient
  58. EP251118a: Continued Optical Detection with Kinder observations
  59. GRB 251121A: Swift/BAT-GUANO localization skymap of a short burst
  60. GRB 251115A: Fermi GBM Observation
  61. EP251118A: 1.3m DFOT optical afterglow detection
  62. GRB 251118A: Glowbug gamma-ray detection
  63. GRB 251118A: Fermi GBM Observation
  64. GRB 251118A: Swift-XRT afterglow detection
  65. GRB 251103A: SVOM/ECLAIRs and SVOM/GRM joint refined analysis
  66. EP251118a: Optical detection with Kinder observations
  67. EP251118a / GRB 251118C: SVOM/VT optical observation
  68. GRB 251118A: NuSTAR detection of bright prompt emission
  69. Konus-Wind detection of GRB 251118C (EP251118a)
  70. GRB 251116D: SVOM/GRM observation of a long GRB
  71. EP251118a: Global MASTER-Net observations report
  72. EP251118a: preliminary result of EP-FXT follow-up observation
  73. LAT GRB251118.86: Global MASTER-Net observations report
  74. GRB 251118A: Fermi-LAT detection
  75. GRB 251118A: BALROG localization (Fermi Trigger 785190695 / GRB 251118855)
  76. GRB 251118A: Fermi GBM Final Real-time Localization
  77. GRB 251013C: Koshka, SAO RAS, Mondy, and CrAO optical observations, possible SN detection
  78. GRB 251117A: Swift/BAT-GUANO localization skymap of a short burst
  79. GRB 251117A: Fermi-LAT detection
  80. LAT GRB251117.51: Global MASTER-Net observations report
  81. GRB 251116C: Swift/BAT arcminute localization of a burst
  82. LIGO/Virgo/KAGRA S251112cm: J-GEM follow-up observations
  83. GRB 251116C: Swift-XRT observations
  84. EP251023a: Assy AZT-20 optical observations
  85. GRB 251116D: AstroSat CZTI detection
  86. GRB 251025B: further Mondy optical observations
  87. SVOM GRB251116C: Global MASTER-Net observations report
  88. GRB 251116C: SVOM detection of a burst
  89. GRB 251115A: Fermi-LAT detection
  90. Fermi GRB 251115A: Global MASTER-Net observations report
  91. LIGO/Virgo/KAGRA S251112cm: NED Galaxies in the 4-Update Localization Volume
  92. GRB 251115A: Fermi GBM Final Real-time Localization
  93. GRB 251113A: AstroSat CZTI detection
  94. GRB 251114B: Fermi GBM Final Real-time Localization
  95. Konus-Wind detection of GRB 251108C
  96. Konus-Wind detection of GRB 251103A
  97. LIGO/Virgo/KAGRA S251112cm: ATLAS targeted observations of the skymap
  98. LIGO/Virgo/KAGRA S251112cm: Swift XRT observations, 20 X-ray sources
  99. GRB 251111A: SVOM/ECLAIRs refined analysis
  100. GRB 251108C: AstroSat CZTI detection

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