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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"

19320 results found.

  1. IceCube-251218A: COLIBRÍ optical upper limits
  2. SVOM GRB251219.11: Global MASTER-Net observations report
  3. IceCube Alert 251218.85: Global MASTER-Net observations report
  4. Fermi trigger No 787736968: Global MASTER-Net observations report
  5. Fermi GRB 251217A: Global MASTER-Net observations report
  6. GRB 251215A: Fermi GBM Observation
  7. Fermi GRB 251216A: Global MASTER-Net observations report
  8. GRB 251215A: Swift-XRT observations
  9. Fermi GRB 251215A: Global MASTER-Net observations report
  10. EP251214a: Optical upper limit with Kinder observations
  11. GRB 251215A: Glowbug gamma-ray detection
  12. GRB 251214B: VLT/X-shooter observations
  13. GRB 251214B: Swift-BAT refined analysis
  14. GRB 251202A: radio detection with the VLA
  15. EP251214b: Global MASTER-Net observations report
  16. GRB 251214B: LCO detection of the optical counterpart
  17. GRB 251214B: Fermi GBM Observation
  18. EP251214b (EP trigger 01709250023): LCO optical limits
  19. GRB 251215A: Swift/BAT-GUANO arcminute localization of a burst
  20. GRB 251214B: Swift-XRT refined Analysis
  21. GRB 251214D: AstroSat CZTI detection of a long burst
  22. GRB 251213A: AstroSat CZTI detection
  23. GRB 251214A: AstroSat CZTI detection
  24. GRB 251213A: GECAM-B detection
  25. EP251214a: Global MASTER-Net observations report
  26. GRB 251214B: Enhanced Swift-XRT position
  27. GRB 251214B : MASTER optical afterglow detection
  28. Fermi trigger No 787396657: Global MASTER-Net observations report
  29. GRB 251214B: SVOM/C-GFT optical observations
  30. Swift GRB 251214B: Global MASTER-Net observations report
  31. Fermi GRB 251214A: Global MASTER-Net observations report
  32. EP251212a: Global MASTER-Net observations report
  33. EP251212a / GRB 251212A: AstroSat CZTI detection
  34. GRB 251211B: AstroSat CZTI detection
  35. GRB 251209A: NuSTAR detection of prompt emission
  36. Fermi-LAT Gamma-ray Observations of IceCube-251210A
  37. IceCube-251210A: Upper limits from a search for additional neutrino events in IceCube
  38. Fermi GRB 251211B: Global MASTER-Net observations report
  39. SVOM GRB251211.12: Global MASTER-Net observations report
  40. GRB 251209A: Fermi GBM observation
  41. GRB 251209A: AstroSat CZTI detection
  42. IceCube Alert 251210.46: Global MASTER-Net observations report
  43. GRB 251208A: AstroSat CZTI detection
  44. Fermi GBM Sub-Threshold Detection of GRB 251205A
  45. GRB 251208A: Glowbug gamma-ray detection
  46. Fermi GRB 251209A: Global MASTER-Net observations report
  47. Fermi GRB 251208C: Global MASTER-Net observations report
  48. GRB 251208B: Swift-XRT afterglow detection
  49. GRB 251208D: LCO analysis of the XRT sources
  50. GRB 251208B: Fermi GBM Observation
  51. GRB 251208B: GROWTH-India Telescope optical upper limits
  52. GRB 251205A: J-band detection with WINTER
  53. GRB 251208D: Swift-XRT observations
  54. GRB 251208A: SVOM/GRM observation of a short burst
  55. GRB 251129A: e-MERLIN C-band observations
  56. LAT GRB251208.43: Global MASTER-Net observations report
  57. SVOM GRB251208D: Global MASTER-Net observations report
  58. GRB 251208B: Fermi-LAT detection
  59. GRB 251208B: Swift/BAT-GUANO arcminute localization of a burst
  60. GRB 251208D: SVOM possible detection of a faint burst
  61. GRB 251206A: SVOM detection of a burst through offline search
  62. SVOM GRB251206.86: Global MASTER-Net observations report
  63. GRB 251205A: ZTF and ATLAS optical afterglow detections
  64. GRB 251205A: Swift-BAT refined analysis
  65. GRB 251205A: Swift-XRT refined Analysis
  66. GRB 251205A: Enhanced Swift-XRT position
  67. Swift GRB 251205A : MASTER OT detection with host galaxy
  68. GRB 251205A: Swift detection of a burst with an optical afterglow
  69. Swift GRB251205A: Global MASTER-Net observations report
  70. GRB 251203C: SVOM/ECLAIRs refined analysis
  71. SVOM/sb25120502: SVOM detection of a faint X-ray transient candidate
  72. GRB 251202A / EP251202a: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 40-cm and 1-m telescopes at McDonald Observatory
  73. GRB 251203A: GECAM-B observation of a burst
  74. GRB 251203C: J-band observations with WINTER
  75. GRB 251129B: Glowbug gamma-ray detection of a short burst
  76. GRB 251203A: AstroSat CZTI detection
  77. GRB 251203C: EP-FXT follow-up observation
  78. GRB 251203B: Swift-XRT observations
  79. GRB 251203B: confirmation of a stellar flare by BOOTES-2
  80. GRB 251203B: SVOM/VT optical observation
  81. SVOM GRB251203.77: Global MASTER-Net observations report
  82. SVOM GRB251203B: Global MASTER-Net observations report
  83. GRB 251201B: Fermi GBM Observation
  84. EP251130a: ULL-ASTRO-MASTER late detection of the optical afterglow with LCO 1-m telescope at Teide Observatory
  85. Fermi GRB 251202B: Global MASTER-Net observations report
  86. GRB 251202A: Fermi GBM Observation
  87. GRB 251130B: Glowbug gamma-ray detection
  88. EP251130a: continued NOT optical observations indicate steep fading phase
  89. Fermi-LAT Gamma-ray Observations of IceCube-251130A
  90. GRB 251202A: Swift-XRT afterglow detection
  91. Fermi GRB 251202A: Global MASTER-Net observations report
  92. GRB 251201B: Swift-XRT refined Analysis
  93. IceCube-251130A: Upper limits from a search for additional neutrino events in IceCube
  94. Swift GRB 251201B : MASTER optical counterpart detection
  95. GRB 251201B: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 1-m telescope at Sutherland Observatory
  96. Swift GRB 251201B: Global MASTER-Net observations report
  97. GRB 251130B: AstroSat CZTI detection
  98. GRB 251201B: Swift detection of a burst with an optical counterpart
  99. GRB 251201B: Fermi GBM Final Real-time Localization
  100. EP251130a: Optical detections with Kinder observations

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