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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"

19952 results found.

  1. GRB 250129A: LCO late afterglow detection
  2. GRB 250129A: COLIBRÍ/DDRAGO Afterglow Detection
  3. GRB 250129A: 7DT Detection and Medium-band SED of Afterglow
  4. GRB 250129A: SVOM/C-GFT optical observations
  5. Swift GRB250129A: MASTER 4 days observations report
  6. Konus-Wind detection of GRB 250129A
  7. GRB 250129A: 1.3m DFOT Optical observations
  8. GRB 250129A: Calapai Observatory, Massa S. Giorgio (Messina), optical observations
  9. GRB 250129A: COLIBRÍ Continuing Detection of the Afterglow
  10. GRB 250129A: COLIBRÍ Optical Observations
  11. GRB 250129A: TNG NIR afterglow detection
  12. GRB 250129A: GRANDMA/TAROT optical afterglow detection
  13. GRB 250127A: EP-FXT second observation epoch and confirmation of the x-ray afterglow fading
  14. GRB 250128B: VLA radio upper limit
  15. Ep250125A: 1.3m DFOT optical upper limit
  16. GRB 250129A: Skynet optical observations
  17. GRB 250129A: KAIT optical observations of the rebrightening around 5.1 hours
  18. GRB 250129A: Swift-XRT refined Analysis
  19. GRB 250128B: TNG optical upper limit
  20. GRB 250129A: Swift/UVOT Detection
  21. GRB 250127A: CrAO and Terskol optical upper limits
  22. GRB 250129A: Enhanced Swift-XRT position
  23. GRB 250128B: NOT optical upper limit
  24. GRB 250129A: REM optical/NIR afterglow detection
  25. GRB 250129A: Early afterglow detection by LCO.
  26. Swift GRB 250129A: Global MASTER-Net Slowly evolving LC detection
  27. GRB 250129A: LCO optical observations
  28. GRB 250129A: GOTO optical observations show brightening afterglow
  29. Swift GRB 250129A: Global MASTER-Net observations report
  30. GRB 250128B: Enhanced Swift-XRT position
  31. GRB 250129A: Swift detection of a burst with an optical counterpart
  32. Swift GRB 250129A: Global MASTER-Net OT detection
  33. GRB 250128B: Swift-XRT refined Analysis
  34. GRB 250128B: Fermi GBM Observation
  35. GRB 250128B: GOTO optical upper limit
  36. Swift GRB 250128B: Global MASTER-Net observations report
  37. EP250125a: Upper limits from Swift/BAT-GUANO
  38. GRB 250128B: LCO optical observations
  39. GRB 250128B: Swift detection of a short burst
  40. GRB 250127A: Swift-XRT observations
  41. GRB 250127A: EP-FXT afterglow detection
  42. GRB 250117A: Fermi GBM Observation
  43. GRB 250127A: SVOM/VT upper limit
  44. IPN triangulation of GRB 250119C
  45. GRB 250127A: Swift ToO observations
  46. GECAM-A detection of a bright burst from SGR 1E1841-045
  47. GRB 250118A: Fermi GBM Observation
  48. EP250125a: REM optical counterpart detection
  49. GRB 250119C: Fermi GBM Observation
  50. EP250125a: Swift/XRT detection of a fading counterpart
  51. Konus-Wind detection of a bright burst from SGR 1E1841-045 on 2025 January 23
  52. GRB 250121A: Swift/BAT-GUANO localization skymap of a burst
  53. IPN triangulation of a bright burst from SGR 1E1841-045
  54. IPN triangulation of GRB 250118B
  55. Konus-Wind detection of GRB 250119B
  56. IPN triangulation of GRB 250119B
  57. Improved IPN triangulation of GRB 250107C
  58. GRB 250114A: Swift-BAT refined analysis
  59. LIGO/Virgo S250119cv: Swift XRT observations, 5 X-ray sources
  60. GRB 250119C: Swift/BAT-GUANO localization skymap of a short burst
  61. GRB 250119B: Swift/BAT-GUANO localization skymap of a long burst
  62. GRB 250118A: Swift/BAT-GUANO localization skymap of a short burst
  63. Konus-Wind detection of GRB 250117A
  64. IPN triangulation of GRB 250117A (short)
  65. GRB 250117A: SVOM/GRM observation of a short burst
  66. GRB 250117A: Swift/BAT-GUANO localization skymap of a short burst
  67. GRB 250116A: GECAM-B detection of a long burst
  68. Swift Trigger 1282245 is not a GRB
  69. GRB 250114B: Swift-XRT afterglow detection
  70. GRB 250101A: Calapai Observatory, Massa S. Giorgio (Messina), optical observations and rebrightening.
  71. IPN triangulation of GRB 250113A
  72. GRB 250114B: Swift-XRT observations
  73. GRB 250114A: LCO optical counterpart detection.
  74. GRB 250114A: GRANDMA/TAROT optical afterglow detection
  75. GRB 250114A: Swift-XRT refined Analysis
  76. GRB 250114A: LCOGT optical afterglow i-band detection
  77. GRB 250114B: Swift ToO observations
  78. EP250111a: SAO RAS optical upper limit
  79. GRB 250114A: Enhanced Swift-XRT position
  80. GRB 250114A: REM detection of the optical and NIR counterpart
  81. Swift GRB250114A: Global MASTER-Net OT detection
  82. GRB 250114A: LCO optical observations
  83. GRB 250114A: TRT optical observations
  84. Swift GRB 250114A: Global MASTER-Net observations report
  85. GRB 250114A: Swift detection of a burst with an optical counterpart
  86. GRB 250107A: VZLUSAT-2 detection
  87. GRB 250109A / EP250109a: GRBAlpha detection
  88. GRB 250106A: Swift-XRT afterglow detection
  89. GRB 250109A / EP250109a: Mephisto optical upper limits
  90. EP250111a: Swift/XRT detection and fading
  91. EP250108a / AT 2025kg: Swift UVOT detections
  92. GRB 250109A / EP250109A: Swift/BAT-GUANO localization skymap of a burst
  93. GRB 250109A / EP250109a: Swift detection of the X-ray afterglow
  94. GRB 250108A: Swift/XRT afterglow fading
  95. EP250109a / GRB 250109A: refined EP-WXT analysis and EP-FXT follow-up observation
  96. EP250109a: Swift/UVOT non-detection
  97. IPN triangulation of GRB 250107D (short/hard)
  98. IPN triangulation of GRB 250107C
  99. GRB 250108B: Swift-BAT refined analysis
  100. GRB 250108B: 1.3m DFOT upper limit

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