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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"

19663 results found.

  1. GRB 190203A: Swift-BAT refined analysis
  2. GRB 190204A: Swift-BAT refined analysis
  3. Konus-Wind observation of GRB 190204A
  4. GRB 190203A: AstroSat CZTI detection
  5. GRB190203A: UVOT analysis
  6. GRB 190204A: Swift/UVOT Detection
  7. GRB 190204A: Enhanced Swift-XRT position
  8. Konus-Wind observation of GRB 190203A
  9. GRB 190203A: Swift-XRT refined Analysis
  10. GRB 190204A: Swift-XRT refined Analysis
  11. GRB 190204A: AstroSat CZTI detection
  12. Swift Trigger 887541: MASTER inspect
  13. GRB 190204A: MAXI/GSC detection
  14. GRB 190202A: R and I band observation from HCT
  15. GRB 190204A: Swift detection of a burst with a possible optical counterpart
  16. Swift Trigger 887541: MASTER optical observation
  17. GRB 190203A: MASTER OT detection
  18. Swift Trigger 887541: Swift detection of Swift J1728.9-3613
  19. GRB 190203A: Enhanced Swift-XRT position
  20. GRB 190203A: Swift detection of a burst with an optical counterpart
  21. GRB 190202A: Swift-XRT refined Analysis
  22. GRB 190202A: LCO-CTIO optical observations
  23. GRB 190202A: Fermi GBM observation
  24. GRB 190202A, Swift-BAT refined analysis
  25. GRB 190202A: AGILE ratemeters detection
  26. GRB 190202A: Swift/UVOT Detection
  27. GRB 190202A: GOTO optical observations
  28. GRB 190202A: Enhanced Swift-XRT position
  29. GRB 190202A: Swift detection of a burst with an optical counterpart
  30. Improved IPN error box for GRB 190129B
  31. GRB 190129B: Swift/UVOT Upper Limits
  32. GRB 190129B: AstroSat CZTI detection
  33. GRB 190129B: MASTER Global Robotic Net optical observation
  34. GRB 190129B: Swift-XRT candidate afterglow detection
  35. GRB 190129B: Tiled Swift observations
  36. Trigger 886496: Another Swift trigger on MAXI J1348-630
  37. Swift Trigger 886157: MASTER optical observation
  38. Trigger 886486: Swift detection of MAXI J1631-479
  39. Trigger 886266: Another Swift trigger on MAXI J1348-630
  40. Swift Trigger 886157: Swift detection of a new transient Swift J1728.9-3613
  41. Swift Trigger 885960: A third Swift trigger on MAXI J1348-630
  42. Trigger 885845: A second Swift trigger on MAXI J1348-630
  43. Trigger 885807: Swift detection of MAXI J1348-630
  44. GRB 190117A: AstroSat CZTI detection
  45. GRB 190123A: AROMA-N Optical Observation
  46. GRB 190123A: Swift/UVOT Upper Limits
  47. GRB 190123A: Swift-BAT refined analysis
  48. GRB 190123A: GMG observational limit
  49. Trigger 885456: Swift detection of MAXI J1631-479
  50. GRB 190123A: Swift-XRT refined Analysis
  51. GRB 190123A: GOTO optical limit
  52. GRB 190123A: Fermi GBM observation
  53. GRB 190123A: BOOTES-4/MET optical limit
  54. GRB 190123A: Enhanced Swift-XRT position
  55. GRB 190123A: MASTER Global Robotic Net optical observation
  56. GRB 190123A: Swift detection of a burst
  57. IPN Triangulation of GRB 190118A (long)
  58. IPN Triangulation of GRB 190117A (long)
  59. Trigger 884906: Swift detection of MAXI J1631-479
  60. Swift ToO Instructions Update
  61. Swift ToO Website Down
  62. GRB 190106A: Discovery Channel Telescope observations
  63. Konus-Wind observation of GRB 190114C
  64. The Swift-XRT WT mode spectrum of GRB190114C
  65. GRB190114C, Long follow up urged
  66. GRB 190114B: Swift-XRT refined Analysis
  67. GRB 190114C: Swift/UVOT Detection
  68. GRB 190114C: Swift-BAT refined analysis
  69. GRB 190114B, Swift-BAT refined analysis
  70. GRB 190114B: Swift/UVOT Upper Limits
  71. GRB 190114A: Swift/UVOT Observations
  72. GRB 190114C:Insight-HXMT/HE detection
  73. GRB 190114C: AGILE/MCAL detection
  74. GRB 190114C: X-shooter observations of a highly extinguished afterglow
  75. GRB 190114C: Fermi-LAT detection
  76. GRB 190114C: Fermi GBM detection
  77. GRB 190114C: Swift-XRT refined Analysis
  78. GRB 190114C: Enhanced Swift-XRT position
  79. GRB 190114C: GROND detection of the afterglow
  80. MAGIC detects the GRB 190114C in the TeV energy domain
  81. GRB 190114B: BOOTES-4/MET optical afterglow detection
  82. GRB 190114C: MASTER 4-polarizations filters OT detection
  83. GRB 190114B: Enhanced Swift-XRT position
  84. GRB 190114C: MASTER afterglow Detection
  85. GRB 190114C: Swift detection of a very bright burst with a bright optical counterpart
  86. GRB 190114A: OSN Detection
  87. GRB 190114B: Swift detection of a burst
  88. GRB 190114A: Swift-BAT refined analysis
  89. GRB 190103B: Swift/UVOT Upper Limits
  90. GRB 190114A: Swift-XRT refined Analysis
  91. GRB 190114A: GROND detection of the afterglow
  92. GRB 190114A: Enhanced Swift-XRT position
  93. GRB 190114A: VLT/X-shooter redshift
  94. GRB 190114A: Prompt enhanced Swift-XRT position
  95. GRB 190114A: Possible UVOT Detection
  96. GRB 190114A: Swift detection of a burst
  97. GRB 190110A：Insight-HXMT/HE detection
  98. Konus-Wind observation of GRB 190110A
  99. GRB 190110A, Swift-BAT refined analysis
  100. Correction to GCN Circular 23663: GRB 190109A: Swift UVOT Upper Limits

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