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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

12283 results found.

  1. Fermi GRB 260514A: Global MASTER-Net observations report
  2. GRB 260512A: AstroSat CZTI detection
  3. GRB 260514A: Fermi GBM Final Real-time Localization
  4. Fermi GRB 260513A: Global MASTER-Net observations report
  5. Fermi GRB 260512A: Global MASTER-Net observations report
  6. GRB 260511B: further SAO RAS optical observations
  7. GRB 260513A: Fermi GBM Final Real-time Localization
  8. Konus-Wind detection of GRB 260511B
  9. GRB 260511B: further J-band observations by the SYSU 80 cm infrared telescope
  10. GRB 260511B: Calapai Observatory, Massa S. Giorgio (Messina), optical observation.
  11. GRB 260512A: NuSTAR detection of prompt emission
  12. GRB 260510C: Infrared J and Hs detections with MDM/MIRAGE
  13. GRB 260512A: Fermi GBM Final Real-time Localization
  14. GRB 260511A: Glowbug gamma-ray detection
  15. Konus-Wind detection of GRB 260511A
  16. MASS-Cube (GRID 2.0) detection of GRB 260511A
  17. MASS-Cube (GRID 2.0) detection of GRB 260507A
  18. GRB 260511B: SAO RAS optical observations
  19. GRB 260510D: Glowbug gamma-ray detection of a likely short burst
  20. GRB 260511B: FRAM-ORM optical detection
  21. GRB 260511A: EP-FXT follow-up observation
  22. GRB 260511B: EP-FXT follow-up observation
  23. GRB 260511B: LCO optical counterpart detection
  24. GRB260511B: MAO/AZT-22 optical observations
  25. GRB 260511A: SVOM/VT optical observations
  26. GRB 260511B: LCO optical observations
  27. GRB 260511B: OHP/T193 spectroscopic observations
  28. GRB 260511B: GOTO optical counterpart detection
  29. GRB 260511B: Xinglong 2.16m/BEFOSC redshift confirmation
  30. GRB 260510C: SVOM/COLIBRÍ (FM-GFT) further optical observations
  31. GRB 260511B: SVOM/VT optical observations
  32. GRB 260511B: SVOM/COLIBRÍ (FM-GFT) optical observations
  33. GRB 260511B: OSIRIS+/GTC redshift z=2.006
  34. GRB 260510C: Fermi GBM Observation
  35. GRB 260511A: REM near-infrared detection
  36. GRB 260511B: GROWTH-India Telescope optical observations
  37. GRB 260511B: AstroSat CZTI detection
  38. GRB 260506B: Glowbug gamma-ray detection
  39. GRB 260506A: Glowbug gamma-ray detection of a short burst
  40. GRB 260511B: J-band observations by the SYSU 80 cm infrared telescope
  41. GRB 260511B: NuSTAR detection of prompt emission
  42. GRB 260511A: NuSTAR detection of prompt emission
  43. GRB 260511B: Fermi GBM Detection
  44. GRB 260511C: Fermi GBM Final Real-time Localization
  45. GRB 260511B: SVOM/VT optical observation with VHF data
  46. GRB 260511B: TRT optical observation
  47. GRB 260511A: Fermi GBM Detection
  48. GRB 260511A: UTGO H50 optical afterglow observation
  49. GRB 260510C: AstroSat CZTI detection
  50. GRB 260511B: SVOM detection of a burst
  51. GRB 260511B: Fermi GBM Final Real-time Localization
  52. GRB 260510C: EP-FXT follow-up observation
  53. GRB 260510C: SVOM/VT optical counterpart confirmation
  54. GRB 260511A: SVOM/VT optical observation with VHF data
  55. Fermi GRB 260511A: Global MASTER-Net observations report
  56. GRB 260511A: KAIT optical afterglow observations
  57. GRB 260511A: LCO optical afterglow detection
  58. GRB 260511A: SVOM/COLIBRÍ (FM-GFT) optical counterpart
  59. GRB 260511A: TRT optical counterpart detection
  60. GRB 260511A: SVOM detection of a bright burst
  61. GRB 260511A: BALROG localization (Fermi Trigger 800172815 / GRB 260511259)
  62. GRB 260510C: SVOM/COLIBRÍ (FM-GFT) optical counterpart candidate
  63. GRB 260511A: Fermi GBM Final Real-time Localization
  64. GRB 260510B: SVOM/VT optical upper limits
  65. GRB 260510C: SVOM/VT optical upper limits
  66. GRB 260510C: MAXI/GSC detection
  67. Fermi GBM Sub-Threshold Detection of GRB 260510B
  68. GRB 260510D: Fermi GBM Final Real-time Localization
  69. GRB 260510C: SVOM detection of a burst
  70. GRB 260510C: Fermi GBM Final Real-time Localization
  71. GRB 260510A: GECAM-B observation
  72. Fermi GRB 260510A: Global MASTER-Net observations report
  73. GRB 260510A: Fermi GBM Final Real-time Localization
  74. GRB 260506B: AstroSat CZTI detection
  75. IceCube-260504A: Upper limits from a search for additional neutrino events in IceCube
  76. GRB 260507B / EP260507a: Fermi-GBM Sub-Threshold Detection
  77. GRB 260507A: Fermi GBM Final Real-time Localization
  78. GRB 260506B: BALROG localization (Fermi Trigger 799765648 / GRB 260506547)
  79. GRB 260506B: Fermi GBM Final Real-time Localization
  80. Fermi GRB 260506A: Global MASTER-Net observations report
  81. GRB 260506A: Fermi GBM Final Real-time Localization
  82. GRB 260503A: GECAM-B observation of a burst
  83. GRB 260421B: radio observation with the VLA
  84. Fermi-LAT Gamma-ray Observations of IceCube-260504A
  85. GRB 260502A: SVOM/GRM observation of a short GRB
  86. GRB 260503A: SVOM/GRM observation of a GRB
  87. IceCube-260504A - IceCube observation of a high-energy neutrino candidate track-like event
  88. GRB 260310A / AT2026fgk: photometric monitoring and tentative maximum of a possible SN
  89. IPN triangulation of GRB 260429A
  90. IPN triangulation of GRB 260428A
  91. Fermi GRB 260504A: Global MASTER-Net observations report
  92. GRB 260504A: Fermi GBM Final Real-time Localization
  93. GRB 260503A: Fermi GBM Final Real-time Localization
  94. GRB 260502A: GECAM-B observation of a short burst
  95. GRB 260502A: Fermi GBM Final Localization
  96. GRB 260429A: SVOM/GRM observation of a short burst
  97. GRB 260429A: Fermi GBM Detection
  98. Fermi GRB 260429A: Global MASTER-Net observations report
  99. GRB 260429A: Fermi GBM Final Real-time Localization
  100. GRB 260428A: SVOM/GRM observation of a possible short burst with extended emission

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