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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"

41948 results found.

  1. GRB 251026A: Swift-XRT observations
  2. GRB 251025B: OHP/T193 optical detection
  3. GRB 251025B: J-band detection with WINTER
  4. GRB 251026A: SVOM/C-GFT upper limit
  5. IceCube-251025A: DDOTI Optical Upper Limit
  6. GRB 251026A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  7. GRB 251026B: Fermi GBM Final Localization
  8. GRB 251026A: SVOM detection of a long burst
  9. GRB 251025B: SVOM/VT optical bump
  10. GRB 251025B: SVOM/COLIBRÍ (FM-GFT) strong rebrightening of the optical counterpart
  11. GRB 251023A: SVOM/GRM observation
  12. GRB 251025B: ULL-ASTRO-MASTER optical counterpart detection with IAC80 telescope at Teide Observatory
  13. GRB 251025C: Fermi GBM Final Real-time Localization
  14. Konus-Wind detection of GRB 251016B
  15. GRB 251025B: GROWTH-India Telescope optical observations
  16. GRB 251024A: Swift/UVOT Upper Limits
  17. GRB 251025B: Swift-XRT afterglow detection
  18. GRB 251024A: Swift-BAT refined analysis
  19. IceCube Alert 251025.57: Global MASTER-Net observations report
  20. GRB 251024A: Swift-XRT refined Analysis
  21. GRB 251025A (sb25102501): stellar flare confirmed
  22. GRB 251025B: SVOM/VT optical observations with VHF data
  23. GRB 251025B: MASTER OT detection
  24. GRB 251025B: SVOM/C-GFT optical counterpart detection
  25. GRB 251025B: SVOM detection of a burst
  26. IceCube-251025A - IceCube observation of a high-energy neutrino candidate track-like event
  27. GRB 251025A (sb25102501): Likely a stellar flare by SVOM/VT
  28. GRB 251025A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  29. GRB 251025A: SVOM/VT VHF optical upper limit
  30. GRB 251025A: SVOM detection of a faint burst
  31. GRB 251003A: VLA Detection
  32. GRB 251024A: Enhanced Swift-XRT position
  33. GRB 251023C: Glowbug gamma-ray detection
  34. GRB 251024A: LCOGT Optical Afterglow Detection
  35. GRB 251022A: KAIT optical observations
  36. GRB 251024A: Swift detection of a burst
  37. Swift GRB 251024A: Global MASTER-Net observations report
  38. GRB 251023B / EP251023b: COLIBRÍ Confirmation of the Fading Nature of the Optical Candidate
  39. GRB 251022A: COLIBRÍ Further Multi-frequency Optical Observations
  40. EP251023a: MAO/AZT-22 optical observations
  41. GRB 251023B: OHP/T193 optical observations
  42. EP251023a: OHP/T193 optical observations
  43. GRB 251023C: AstroSat CZTI detection
  44. EP251023b/GRB 251023B: JinShan optical observation
  45. GRB 251022A: Swift-XRT detection of GOTO25iym
  46. EP251023b: Global MASTER-Net observations report
  47. EP251023b/GRB 251023B : Einstein Probe detection of a fast X-ray transient
  48. GRB 251022A: GROWTH-India Telescope optical observations
  49. GRB 251023C: Swift/BAT-GUANO localization skymap of a burst
  50. EP251023a: GROWTH-India Telescope optical observations
  51. GRB 251022A: Fermi GBM Observation
  52. GRB 251022A: Swift/BAT-GUANO localization skymap of a burst
  53. GRB 251023A: Glowbug gamma-ray detection
  54. GRB 251023B: Glowbug gamma-ray detection
  55. EP251023a: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 40-cm telescope at Teide Observatory
  56. EP251023a: Global MASTER-Net observations report
  57. GRB 251023B / EP#01709247298: COLIBRÍ optical counterpart candidate
  58. EP#01709247298: Swift-XRT counterpart detection
  59. EP251023a: COLIBRÍ optical observations
  60. GRB 251013C: further SAO RAS optical observations
  61. EP251023a: Keck/LRIS spectroscopic redshift z=2.232
  62. GRB 251022A: COLIBRÍ optical observations
  63. GRB 251013C: ISON-Castelgrande observatory optical observations
  64. GRB 251022A: MASTER OT detection
  65. GRB 251022A: DDOTI Optical Detection
  66. EP251021b/GRB 251021A: SVOM/VT optical candidate
  67. GRB 251023B / MAXI J0451+122: MAXI/GSC detection
  68. EP251023a: NOT optical counterpart detection
  69. Fermi GRB 251023A: Global MASTER-Net observations report
  70. EP251023a: GSP Optical Counterpart Detection
  71. EP251023a: Einstein Probe detection of an X-ray transient
  72. EP/WXT 01709247295: GOTO optical afterglow candidate.
  73. GRB 251022A: GOTO optical counterpart detection
  74. GRB 251023A: Fermi GBM Final Localization Correction
  75. GRB 251022A: Fermi-LAT detection
  76. GRB 251016B: Fermi GBM Detection
  77. GRB 251022A: Tiled Swift observations
  78. LAT GRB251022A: Global MASTER-Net observations report
  79. GRB 251022A: Fermi GBM Final Real-time Localization
  80. GRB 251021A/EP251021b: Fermi-GBM Sub-Threshold Detection
  81. EP251021b: Einstein Probe detection of a fast X-ray transient
  82. GRB 250911A: MAXI/GSC detection
  83. GRB 251016A: SVOM/ECLAIRs refined analysis
  84. LIGO/Virgo/KAGRA S251021u: Identification of a GW compact binary merger candidate
  85. Fermi-LAT gamma-ray observations of IceCube-251018A
  86. GRB 251017A : RAPAS follow-up observations
  87. IceCube-251018A: Upper limits from a search for additional neutrino events in IceCube
  88. GRB 251017A: COLIBRÍ optical observations of a late plateau
  89. IceCube-251018A: DDOTI Optical Upper Limit
  90. GRB 251017A: Swift-BAT refined analysis
  91. GRB 251016A: Fermi GBM Observation
  92. GRB 251018A: Fermi GBM Observation
  93. GRB 251018A: BOOTES-5 and BOOTES-7 early optical detections
  94. GRB 251018A: Swift-XRT refined Analysis
  95. GRB 251018A: Enhanced Swift-XRT position
  96. Fermi trigger No 782500909: Global MASTER-Net observations report
  97. GRB 251016A: HXMT/HE detection
  98. IceCube-251018A: Global MASTER-Net observations report
  99. LIGO/Virgo/KAGRA S251018bi: Identification of a GW compact binary merger candidate
  100. GRB 251016A: Swift-XRT afterglow detection

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