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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"

37228 results found.

  1. Konus-Wind detection of GRB 251016A (short/hard)
  2. GRB 251025B: VLT/MUSE spectroscopic redshift z = 2.003
  3. GRB 251027A: SVOM detection of a faint burst
  4. GRB 251026B: Tentative GOTO optical counterpart candidate
  5. GRB 251025C: AstroSat CZTI detection
  6. EP251023a: Mondy optical observations
  7. GRB 251025C: CALET Gamma-Ray Burst Monitor detection
  8. GRB 251025B: MAO/AZT-22 optical observations
  9. Fermi GRB 251026B: Global MASTER-Net observations report
  10. Fermi GRB 251025C: Global MASTER-Net observations report
  11. GRB 251026A: Swift-XRT observations
  12. GRB 251025B: OHP/T193 optical detection
  13. GRB 251025B: J-band detection with WINTER
  14. GRB 251026A: SVOM/C-GFT upper limit
  15. GRB 251026A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  16. GRB 251026B: Fermi GBM Final Localization
  17. GRB 251026A: SVOM detection of a long burst
  18. GRB 251025B: SVOM/VT optical bump
  19. GRB 251025B: SVOM/COLIBRÍ (FM-GFT) strong rebrightening of the optical counterpart
  20. GRB 251023A: SVOM/GRM observation
  21. GRB 251025B: ULL-ASTRO-MASTER optical counterpart detection with IAC80 telescope at Teide Observatory
  22. GRB 251025C: Fermi GBM Final Real-time Localization
  23. Konus-Wind detection of GRB 251016B
  24. GRB 251025B: GROWTH-India Telescope optical observations
  25. GRB 251024A: Swift/UVOT Upper Limits
  26. GRB 251025B: Swift-XRT afterglow detection
  27. GRB 251024A: Swift-BAT refined analysis
  28. GRB 251024A: Swift-XRT refined Analysis
  29. GRB 251025A (sb25102501): stellar flare confirmed
  30. GRB 251025B: SVOM/VT optical observations with VHF data
  31. GRB 251025B: MASTER OT detection
  32. GRB 251025B: SVOM/C-GFT optical counterpart detection
  33. GRB 251025B: SVOM detection of a burst
  34. GRB 251025A (sb25102501): Likely a stellar flare by SVOM/VT
  35. GRB 251025A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  36. GRB 251025A: SVOM/VT VHF optical upper limit
  37. GRB 251025A: SVOM detection of a faint burst
  38. GRB 251003A: VLA Detection
  39. GRB 251024A: Enhanced Swift-XRT position
  40. GRB 251023C: Glowbug gamma-ray detection
  41. GRB 251024A: LCOGT Optical Afterglow Detection
  42. GRB 251022A: KAIT optical observations
  43. GRB 251024A: Swift detection of a burst
  44. Swift GRB 251024A: Global MASTER-Net observations report
  45. GRB 251023B / EP251023b: COLIBRÍ Confirmation of the Fading Nature of the Optical Candidate
  46. GRB 251022A: COLIBRÍ Further Multi-frequency Optical Observations
  47. GRB 251023B: OHP/T193 optical observations
  48. EP251023a: OHP/T193 optical observations
  49. GRB 251023C: AstroSat CZTI detection
  50. EP251023b/GRB 251023B: JinShan optical observation
  51. GRB 251022A: Swift-XRT detection of GOTO25iym
  52. EP251023b/GRB 251023B : Einstein Probe detection of a fast X-ray transient
  53. GRB 251023C: CALET Gamma-Ray Burst Monitor detection
  54. GRB 251022A: GROWTH-India Telescope optical observations
  55. GRB 251023C: Swift/BAT-GUANO localization skymap of a burst
  56. GRB 251022A: Fermi GBM Observation
  57. GRB 251022A: Swift/BAT-GUANO localization skymap of a burst
  58. GRB 251023A: Glowbug gamma-ray detection
  59. GRB 251023B: Glowbug gamma-ray detection
  60. GRB 251023B / EP#01709247298: COLIBRÍ optical counterpart candidate
  61. IPN triangulation of GRB 251016B
  62. GRB 251023B: CALET Gamma-Ray Burst Monitor detection
  63. EP#01709247298: Swift-XRT counterpart detection
  64. GRB 251013C: further SAO RAS optical observations
  65. GRB 251022A: COLIBRÍ optical observations
  66. GRB 251013C: ISON-Castelgrande observatory optical observations
  67. GRB 251022A: MASTER OT detection
  68. GRB 251022A: DDOTI Optical Detection
  69. EP251021b/GRB 251021A: SVOM/VT optical candidate
  70. GRB 251023B / MAXI J0451+122: MAXI/GSC detection
  71. Fermi GRB 251023A: Global MASTER-Net observations report
  72. GRB 251022A: GOTO optical counterpart detection
  73. GRB 251023A: Fermi GBM Final Localization Correction
  74. GRB 251022A: Fermi-LAT detection
  75. GRB 251016B: Fermi GBM Detection
  76. GRB 251022A: Tiled Swift observations
  77. GRB 251022A: Fermi GBM Final Real-time Localization
  78. GRB 251021A/EP251021b: Fermi-GBM Sub-Threshold Detection
  79. EP251021b: BOOTES-7 optical upper limit
  80. GRB 250911A: MAXI/GSC detection
  81. GRB 251016A: SVOM/ECLAIRs refined analysis
  82. GRB 251017A : RAPAS follow-up observations
  83. GRB 251017A: COLIBRÍ optical observations of a late plateau
  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. GRB 251016A: HXMT/HE detection
  91. GRB 251016A: Swift-XRT afterglow detection
  92. GRB 251017A: Swift/UVOT Detection
  93. GRB 251016A: Swift/UVOT Detection
  94. GRB 251018A: Swift/UVOT Detection
  95. GRB 251017A: VLT/MUSE spectroscopic redshift z = 4.327
  96. GRB 251016A: VLT/FORS2 Optical Observation
  97. GRB 251017A: COLIBRÍ photometric redshift
  98. GRB 251017A: Swift-XRT refined Analysis
  99. GRB 251018A: MASTER OT detection
  100. GRB 251018A: TRT optical afterglow detection

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