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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"

37234 results found.

  1. GRB 251017A: Mondy AZT-33IK and Koshka Zeiss-1000 optical observations
  2. GRB 251023B / EP251023b: Mondy optical upper limit
  3. GRB 251017A: INASAN-Kislovodsk optical observations
  4. GRB 251026A: Mondy optical upper limit
  5. GRB 251025B: Mondy optical observations
  6. GRB 251025B: Kilonova-Catcher optical afterglow detection
  7. Konus-Wind detection of GRB 251016A (short/hard)
  8. GRB 251025B: VLT/MUSE spectroscopic redshift z = 2.003
  9. GRB 251027A: SVOM detection of a faint burst
  10. GRB 251026B: Tentative GOTO optical counterpart candidate
  11. GRB 251025C: AstroSat CZTI detection
  12. EP251023a: Mondy optical observations
  13. GRB 251025C: CALET Gamma-Ray Burst Monitor detection
  14. GRB 251025B: MAO/AZT-22 optical observations
  15. Fermi GRB 251026B: Global MASTER-Net observations report
  16. Fermi GRB 251025C: Global MASTER-Net observations report
  17. GRB 251026A: Swift-XRT observations
  18. GRB 251025B: OHP/T193 optical detection
  19. GRB 251025B: J-band detection with WINTER
  20. GRB 251026A: SVOM/C-GFT upper limit
  21. GRB 251026A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  22. GRB 251026B: Fermi GBM Final Localization
  23. GRB 251026A: SVOM detection of a long burst
  24. GRB 251025B: SVOM/VT optical bump
  25. GRB 251025B: SVOM/COLIBRÍ (FM-GFT) strong rebrightening of the optical counterpart
  26. GRB 251023A: SVOM/GRM observation
  27. GRB 251025B: ULL-ASTRO-MASTER optical counterpart detection with IAC80 telescope at Teide Observatory
  28. GRB 251025C: Fermi GBM Final Real-time Localization
  29. Konus-Wind detection of GRB 251016B
  30. GRB 251025B: GROWTH-India Telescope optical observations
  31. GRB 251024A: Swift/UVOT Upper Limits
  32. GRB 251025B: Swift-XRT afterglow detection
  33. GRB 251024A: Swift-BAT refined analysis
  34. GRB 251024A: Swift-XRT refined Analysis
  35. GRB 251025A (sb25102501): stellar flare confirmed
  36. GRB 251025B: SVOM/VT optical observations with VHF data
  37. GRB 251025B: MASTER OT detection
  38. GRB 251025B: SVOM/C-GFT optical counterpart detection
  39. GRB 251025B: SVOM detection of a burst
  40. GRB 251025A (sb25102501): Likely a stellar flare by SVOM/VT
  41. GRB 251025A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  42. GRB 251025A: SVOM/VT VHF optical upper limit
  43. GRB 251025A: SVOM detection of a faint burst
  44. GRB 251003A: VLA Detection
  45. GRB 251024A: Enhanced Swift-XRT position
  46. GRB 251023C: Glowbug gamma-ray detection
  47. GRB 251024A: LCOGT Optical Afterglow Detection
  48. GRB 251022A: KAIT optical observations
  49. GRB 251024A: Swift detection of a burst
  50. Swift GRB 251024A: Global MASTER-Net observations report
  51. GRB 251023B / EP251023b: COLIBRÍ Confirmation of the Fading Nature of the Optical Candidate
  52. GRB 251022A: COLIBRÍ Further Multi-frequency Optical Observations
  53. GRB 251023B: OHP/T193 optical observations
  54. EP251023a: OHP/T193 optical observations
  55. GRB 251023C: AstroSat CZTI detection
  56. EP251023b/GRB 251023B: JinShan optical observation
  57. GRB 251022A: Swift-XRT detection of GOTO25iym
  58. EP251023b/GRB 251023B : Einstein Probe detection of a fast X-ray transient
  59. GRB 251023C: CALET Gamma-Ray Burst Monitor detection
  60. GRB 251022A: GROWTH-India Telescope optical observations
  61. GRB 251023C: Swift/BAT-GUANO localization skymap of a burst
  62. GRB 251022A: Fermi GBM Observation
  63. GRB 251022A: Swift/BAT-GUANO localization skymap of a burst
  64. GRB 251023A: Glowbug gamma-ray detection
  65. GRB 251023B: Glowbug gamma-ray detection
  66. GRB 251023B / EP#01709247298: COLIBRÍ optical counterpart candidate
  67. IPN triangulation of GRB 251016B
  68. GRB 251023B: CALET Gamma-Ray Burst Monitor detection
  69. EP#01709247298: Swift-XRT counterpart detection
  70. GRB 251013C: further SAO RAS optical observations
  71. GRB 251022A: COLIBRÍ optical observations
  72. GRB 251013C: ISON-Castelgrande observatory optical observations
  73. GRB 251022A: MASTER OT detection
  74. GRB 251022A: DDOTI Optical Detection
  75. EP251021b/GRB 251021A: SVOM/VT optical candidate
  76. GRB 251023B / MAXI J0451+122: MAXI/GSC detection
  77. Fermi GRB 251023A: Global MASTER-Net observations report
  78. GRB 251022A: GOTO optical counterpart detection
  79. GRB 251023A: Fermi GBM Final Localization Correction
  80. GRB 251022A: Fermi-LAT detection
  81. GRB 251016B: Fermi GBM Detection
  82. GRB 251022A: Tiled Swift observations
  83. GRB 251022A: Fermi GBM Final Real-time Localization
  84. GRB 251021A/EP251021b: Fermi-GBM Sub-Threshold Detection
  85. EP251021b: BOOTES-7 optical upper limit
  86. GRB 250911A: MAXI/GSC detection
  87. GRB 251016A: SVOM/ECLAIRs refined analysis
  88. GRB 251017A : RAPAS follow-up observations
  89. GRB 251017A: COLIBRÍ optical observations of a late plateau
  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. GRB 251016A: HXMT/HE detection
  97. GRB 251016A: Swift-XRT afterglow detection
  98. GRB 251017A: Swift/UVOT Detection
  99. GRB 251016A: Swift/UVOT Detection
  100. GRB 251018A: Swift/UVOT Detection

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