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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"

42476 results found.

  1. GRB 251026A: SVOM detection of a long burst
  2. GRB 251025B: SVOM/VT optical bump
  3. GRB 251025B: SVOM/COLIBRÍ (FM-GFT) strong rebrightening of the optical counterpart
  4. GRB 251023A: SVOM/GRM observation
  5. GRB 251025B: ULL-ASTRO-MASTER optical counterpart detection with IAC80 telescope at Teide Observatory
  6. GRB 251025C: Fermi GBM Final Real-time Localization
  7. Konus-Wind detection of GRB 251016B
  8. GRB 251025B: GROWTH-India Telescope optical observations
  9. GRB 251024A: Swift/UVOT Upper Limits
  10. GRB 251025B: Swift-XRT afterglow detection
  11. GRB 251024A: Swift-BAT refined analysis
  12. IceCube Alert 251025.57: Global MASTER-Net observations report
  13. GRB 251024A: Swift-XRT refined Analysis
  14. GRB 251025A (sb25102501): stellar flare confirmed
  15. GRB 251025B: SVOM/VT optical observations with VHF data
  16. GRB 251025B: MASTER OT detection
  17. GRB 251025B: SVOM/C-GFT optical counterpart detection
  18. GRB 251025B: SVOM detection of a burst
  19. IceCube-251025A - IceCube observation of a high-energy neutrino candidate track-like event
  20. GRB 251025A (sb25102501): Likely a stellar flare by SVOM/VT
  21. GRB 251025A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  22. GRB 251025A: SVOM/VT VHF optical upper limit
  23. GRB 251025A: SVOM detection of a faint burst
  24. GRB 251003A: VLA Detection
  25. GRB 251024A: Enhanced Swift-XRT position
  26. GRB 251023C: Glowbug gamma-ray detection
  27. GRB 251024A: LCOGT Optical Afterglow Detection
  28. GRB 251022A: KAIT optical observations
  29. GRB 251024A: Swift detection of a burst
  30. Swift GRB 251024A: Global MASTER-Net observations report
  31. GRB 251023B / EP251023b: COLIBRÍ Confirmation of the Fading Nature of the Optical Candidate
  32. GRB 251022A: COLIBRÍ Further Multi-frequency Optical Observations
  33. EP251023a: MAO/AZT-22 optical observations
  34. GRB 251023B: OHP/T193 optical observations
  35. EP251023a: OHP/T193 optical observations
  36. GRB 251023C: AstroSat CZTI detection
  37. EP251023b/GRB 251023B: JinShan optical observation
  38. GRB 251022A: Swift-XRT detection of GOTO25iym
  39. EP251023b: Global MASTER-Net observations report
  40. EP251023b/GRB 251023B : Einstein Probe detection of a fast X-ray transient
  41. GRB 251022A: GROWTH-India Telescope optical observations
  42. GRB 251023C: Swift/BAT-GUANO localization skymap of a burst
  43. EP251023a: GROWTH-India Telescope optical observations
  44. GRB 251022A: Fermi GBM Observation
  45. GRB 251022A: Swift/BAT-GUANO localization skymap of a burst
  46. GRB 251023A: Glowbug gamma-ray detection
  47. GRB 251023B: Glowbug gamma-ray detection
  48. EP251023a: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 40-cm telescope at Teide Observatory
  49. EP251023a: Global MASTER-Net observations report
  50. GRB 251023B / EP#01709247298: COLIBRÍ optical counterpart candidate
  51. EP#01709247298: Swift-XRT counterpart detection
  52. EP251023a: COLIBRÍ optical observations
  53. GRB 251013C: further SAO RAS optical observations
  54. EP251023a: Keck/LRIS spectroscopic redshift z=2.232
  55. GRB 251022A: COLIBRÍ optical observations
  56. GRB 251013C: ISON-Castelgrande observatory optical observations
  57. GRB 251022A: MASTER OT detection
  58. GRB 251022A: DDOTI Optical Detection
  59. EP251021b/GRB 251021A: SVOM/VT optical candidate
  60. GRB 251023B / MAXI J0451+122: MAXI/GSC detection
  61. EP251023a: NOT optical counterpart detection
  62. Fermi GRB 251023A: Global MASTER-Net observations report
  63. EP251023a: GSP Optical Counterpart Detection
  64. EP251023a: Einstein Probe detection of an X-ray transient
  65. EP/WXT 01709247295: GOTO optical afterglow candidate.
  66. GRB 251022A: GOTO optical counterpart detection
  67. GRB 251023A: Fermi GBM Final Localization Correction
  68. GRB 251022A: Fermi-LAT detection
  69. GRB 251016B: Fermi GBM Detection
  70. GRB 251022A: Tiled Swift observations
  71. LAT GRB251022A: Global MASTER-Net observations report
  72. GRB 251022A: Fermi GBM Final Real-time Localization
  73. GRB 251021A/EP251021b: Fermi-GBM Sub-Threshold Detection
  74. EP251021b: BOOTES-7 optical upper limit
  75. EP251021b: Einstein Probe detection of a fast X-ray transient
  76. GRB 250911A: MAXI/GSC detection
  77. GRB 251016A: SVOM/ECLAIRs refined analysis
  78. LIGO/Virgo/KAGRA S251021u: Identification of a GW compact binary merger candidate
  79. Fermi-LAT gamma-ray observations of IceCube-251018A
  80. GRB 251017A : RAPAS follow-up observations
  81. IceCube-251018A: Upper limits from a search for additional neutrino events in IceCube
  82. GRB 251017A: COLIBRÍ optical observations of a late plateau
  83. IceCube-251018A: DDOTI Optical Upper Limit
  84. GRB 251017A: Swift-BAT refined analysis
  85. GRB 251016A: Fermi GBM Observation
  86. GRB 251018A: Fermi GBM Observation
  87. GRB 251018A: BOOTES-5 and BOOTES-7 early optical detections
  88. GRB 251018A: Swift-XRT refined Analysis
  89. GRB 251018A: Enhanced Swift-XRT position
  90. Fermi trigger No 782500909: Global MASTER-Net observations report
  91. GRB 251016A: HXMT/HE detection
  92. IceCube-251018A: Global MASTER-Net observations report
  93. LIGO/Virgo/KAGRA S251018bi: Identification of a GW compact binary merger candidate
  94. GRB 251016A: Swift-XRT afterglow detection
  95. GRB 251017A: Swift/UVOT Detection
  96. GRB 251016A: Swift/UVOT Detection
  97. GRB 251018A: Swift/UVOT Detection
  98. IceCube-251018A - IceCube observation of a high-energy neutrino candidate track-like event
  99. GRB 251017A: VLT/MUSE spectroscopic redshift z = 4.327
  100. GRB 251016A: VLT/FORS2 Optical Observation

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