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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"

19610 results found.

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

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