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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"

21526 results found.

  1. GRB 250205A: Swift/UVOT Upper Limits
  2. GRB 250205A: Swift/XRT detection
  3. IPN triangulation of GRB 250201A
  4. GRB 250129A: Swift-BAT refined analysis
  5. IPN triangulation of GRB 250204B (short/hard)
  6. IPN triangulation of GRB 250202B
  7. GRB 250129A: LCO late afterglow detection
  8. GRB 250129A: COLIBRÍ/DDRAGO Afterglow Detection
  9. GRB 250129A: 7DT Detection and Medium-band SED of Afterglow
  10. GRB 250129A: SVOM/C-GFT optical observations
  11. Swift GRB250129A: MASTER 4 days observations report
  12. Konus-Wind detection of GRB 250129A
  13. GRB 250129A: 1.3m DFOT Optical observations
  14. GRB 250129A: Calapai Observatory, Massa S. Giorgio (Messina), optical observations
  15. GRB 250129A: COLIBRÍ Continuing Detection of the Afterglow
  16. GRB 250129A: COLIBRÍ Optical Observations
  17. GRB 250128B: VLA possible radio detection
  18. GRB 250129A: TNG NIR afterglow detection
  19. GRB 250129A: GRANDMA/TAROT optical afterglow detection
  20. GRB 250127A: EP-FXT second observation epoch and confirmation of the x-ray afterglow fading
  21. GRB 250128B: SAO RAS Zeiss-1000 and CrAO ZTSh optical upper limits
  22. GRB 250128B: VLA radio upper limit
  23. Ep250125A: 1.3m DFOT optical upper limit
  24. GRB 250129A: Skynet optical observations
  25. GRB 250129A: KAIT optical observations of the rebrightening around 5.1 hours
  26. GRB 250129A: Swift-XRT refined Analysis
  27. GRB 250128B: Gemini-North optical extended source detection
  28. GRB 250128B: TNG optical upper limit
  29. GRB 250129A: Swift/UVOT Detection
  30. GRB 250128B: VLT/HAWKI near-infrared observations
  31. GRB 250127A: CrAO and Terskol optical upper limits
  32. GRB 250129A: Enhanced Swift-XRT position
  33. GRB 250128B: NOT optical upper limit
  34. GRB 250128B: VLT/FORS2 optical observations
  35. GRB 250129A: REM optical/NIR afterglow detection
  36. GRB 250129A: Early afterglow detection by LCO.
  37. GRB 250128B: OHP/T193 optical upper limit
  38. Swift GRB 250129A: Global MASTER-Net Slowly evolving LC detection
  39. GRB 250129A: LCO optical observations
  40. GRB 250129A: GOTO optical observations show brightening afterglow
  41. Swift GRB 250129A: Global MASTER-Net observations report
  42. GRB 250128B: Enhanced Swift-XRT position
  43. GRB 250129A: Swift detection of a burst with an optical counterpart
  44. Swift GRB 250129A: Global MASTER-Net OT detection
  45. GRB 250128B: Swift-XRT refined Analysis
  46. GRB 250128B: Fermi GBM Observation
  47. GRB 250128B: GOTO optical upper limit
  48. Swift GRB 250128B: Global MASTER-Net observations report
  49. EP250125a: Upper limits from Swift/BAT-GUANO
  50. GRB 250128B: LCO optical observations
  51. GRB 250128B: Swift detection of a short burst
  52. GRB 250127A: Swift-XRT observations
  53. GRB 250127A: EP-FXT afterglow detection
  54. GRB 250117A: Fermi GBM Observation
  55. GRB 250127A: SVOM/VT upper limit
  56. IPN triangulation of GRB 250119C
  57. GRB 250127A: Swift ToO observations
  58. GRB 250118A: Fermi GBM Observation
  59. EP250125a: REM optical counterpart detection
  60. GRB 250119C: Fermi GBM Observation
  61. EP250125a: Swift/XRT detection of a fading counterpart
  62. GRB 250121A: Swift/BAT-GUANO localization skymap of a burst
  63. IPN triangulation of GRB 250118B
  64. Konus-Wind detection of GRB 250119B
  65. IPN triangulation of GRB 250119B
  66. Improved IPN triangulation of GRB 250107C
  67. GRB 250114A: Swift-BAT refined analysis
  68. LIGO/Virgo S250119cv: Swift XRT observations, 5 X-ray sources
  69. GRB 250119C: Swift/BAT-GUANO localization skymap of a short burst
  70. GRB 250119B: Swift/BAT-GUANO localization skymap of a long burst
  71. GRB 250118A: Swift/BAT-GUANO localization skymap of a short burst
  72. Konus-Wind detection of GRB 250117A
  73. IPN triangulation of GRB 250117A (short)
  74. GRB 250117A: SVOM/GRM observation of a short burst
  75. GRB 250117A: Swift/BAT-GUANO localization skymap of a short burst
  76. Swift Trigger 1282245 is not a GRB
  77. GRB 250114B: Swift-XRT afterglow detection
  78. GRB 250101A: Calapai Observatory, Massa S. Giorgio (Messina), optical observations and rebrightening.
  79. IPN triangulation of GRB 250113A
  80. GRB 250114B: Liverpool Telescope optical upper limit
  81. GRB 250114B : MITSuME Akeno optical afterglow candidate detection
  82. GRB 250114B: Swift-XRT observations
  83. GRB 250114A: LCO optical counterpart detection.
  84. GRB 250114B: OHP/T193 optical upper limit
  85. GRB 250114A: GRANDMA/TAROT optical afterglow detection
  86. GRB 250114A: Swift-XRT refined Analysis
  87. GRB 250114A: LCOGT optical afterglow i-band detection
  88. GRB 250114B: Swift ToO observations
  89. EP250111a: SAO RAS optical upper limit
  90. GRB 250114A: Enhanced Swift-XRT position
  91. GRB 250114A: REM detection of the optical and NIR counterpart
  92. Swift GRB250114A: Global MASTER-Net OT detection
  93. GRB 250114A: LCO optical observations
  94. GRB 250114A: TRT optical observations
  95. Swift GRB 250114A: Global MASTER-Net observations report
  96. GRB 250114A: Swift detection of a burst with an optical counterpart
  97. GRB 250107A: VZLUSAT-2 detection
  98. GRB 250109A / EP250109a: GRBAlpha detection
  99. GRB 250106A: Swift-XRT afterglow detection
  100. GRB 250109A / EP250109a: Mephisto optical upper limits

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