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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"

43714 results found.

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

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