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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.

"200205A/SWIFT J0840.7-3516" does not adhere to advanced search syntax. Please refer to the documentation and try again.
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"

19666 results found.

  1. GRB 250924A: NOT optical observations
  2. GRB 250924A: AstroSat CZTI detection
  3. GRB 250920B: AstroSat CZTI detection
  4. GRB 250924A: SVOM/VT optical observation
  5. GRB 250924A: Swift/UVOT Detection
  6. GRB 250924A: Swift-XRT refined Analysis
  7. GRB 250924A: Enhanced Swift-XRT position
  8. GRB 250924A: GROWTH-India Telescope Upper Limits
  9. GRB 250924A: KAIT optical observations
  10. GRB 250924A: Mondy optical observations, afterglow fading
  11. GRB 250924A: Kilonova-Catcher optical afterglow detection
  12. GRB 250920C: Kilonova-Catcher optical afterglow detection
  13. GRB 250920C: TRT optical observation
  14. GRB 250924A: COLIBRÍ optical observations
  15. Swift GRB 250924A: Global MASTER-Net observations report
  16. GRB 250924A: DDOTI Detection of the Optical Counterpart
  17. GRB 250924A: Swift detection of a burst with an optical counterpart
  18. GRB 250920B: AbAO optical upper limits
  19. Konus-Wind detection of GRB 250920C
  20. GRB 250920B: CrAO ZTSH optical observations
  21. GRB 250920C: COLIBRÍ optical observations
  22. GRB 250920C: PRIME near-infrared detection
  23. Konus-Wind detection of GRB 250920B
  24. Konus-Wind detection of GRB 250911A
  25. GRB 250916A: Swift/UVOT Detection
  26. GRB 250920B: Glowbug gamma-ray detection
  27. GRB 250920C: Swift-XRT refined Analysis
  28. GRB 250920B: Kitab-ISON optical upper limit
  29. GRB 250917B: Mondy and Zeiss-1000 SAO RAS optical observations, optical observations, afterglow candidate
  30. GRB 250920C: SVOM/GRM observation
  31. GRB 250920C: GTC/OSIRIS+ spectroscopic redshift z = 1.40
  32. GRB 250917B: KAIT optical upper limit
  33. GRB 250920C: GROWTH-India Telescope optical observations
  34. GRB 250920C: Swift-BAT refined analysis
  35. GRB 250920B: Swift-BAT refined analysis
  36. GRB 250920C: Enhanced Swift-XRT position
  37. GRB 250920C: Swift/UVOT Detection
  38. GRB 250920B: Fermi GBM Observation
  39. GRB 250920C: Fermi GBM Observation
  40. Swift GRB 250920C: Global MASTER-Net observations report
  41. GRB 250920B: Swift/UVOT Detection
  42. GRB 250920C: Optical counterpart detection by LCO
  43. GRB250920C: LCOGT Optical Detection
  44. GRB 250920B: Enhanced Swift-XRT position
  45. GRB 250920B: Swift-XRT refined Analysis
  46. GRB 250920B: SVOM/C-GFT optical observations
  47. GRB 250920C: GOTO optical counterpart candidate
  48. GRB 250920C: Swift detection of a burst
  49. Swift GRB 250920B: Global MASTER-Net observations report
  50. GRB 250920B: Swift detection of a burst with a bright optical counterpart.
  51. GRB 250919A / EP250919a: MASTER bright afterglow detection 24h after GRB time
  52. GRB 250916A: Mondy R-band optical observations
  53. GRB 250919A: Fermi GBM Observation
  54. GRB 250919A/EP250919A: Swift/UVOT afterglow detection
  55. GRB 250919A: Swift-XRT afterglow detection
  56. GRB 250917B: Swift-BAT refined analysis
  57. GRB 250917B: Swift/UVOT Upper Limits
  58. GRB 250916A: Swift-XRT observations
  59. GRB250917B: WFST optical observations
  60. GRB 250916A: Swift ToO observations
  61. GRB 250917B: Fermi GBM Observation
  62. GRB 250917B: Swift-XRT observations
  63. GRB 250917B: Swift detection of a short burst
  64. GRB 250912A: Swift/BAT-GUANO localization skymap of a possibly short burst
  65. GRB 250912A: Swift-XRT observations
  66. GRB 250911A: Insight-HXMT detection
  67. GRB 250911A: GECAM-B detection
  68. GRB 250911A: Swift-BAT refined analysis
  69. EP250911a: refined analysis of the EP-WXT and EP-FXT observations
  70. EP250911a: SVOM/VT optical observation
  71. GRB 250911A: MASTER optical counterpart observations
  72. GRB 250911A: Swift-XRT refined Analysis
  73. EP250911a: Swift-XRT observations
  74. GRB 250911A: Swift/UVOT Detection
  75. GRB 250910A / EP250910a: Swift-XRT afterglow detection
  76. GRB 250910A / EP250910a: SVOM/VT afterglow confirmation
  77. GRB 250910A / EP250910a : VLT/HAWK-I NIR counterpart discovery
  78. GRB 250911A: Enhanced Swift-XRT position
  79. GRB 250911A: Swift-XRT observations
  80. GRB 250911A: COLIBRÍ optical counterpart candidate
  81. GRB 250911A: Swift detection of a burst
  82. GRB 250702B: Late time Chandra observations
  83. EP250908b/EP#01709240653: Swift/UVOT Detection
  84. EP#01709240653: Swift-XRT observations
  85. GRB 250905A: Swift-BAT refined analysis
  86. GRB 250903A: Swift-XRT afterglow detection
  87. GRB 250905A: Swift-XRT refined Analysis
  88. GRB 250904A: Swift-BAT refined analysis
  89. GRB 250905A: Swift/UVOT Upper Limits
  90. GRB 250905A: Enhanced Swift-XRT position
  91. GRB 250904A: Swift/UVOT Detection
  92. GRB 250903A: Swift/UVOT detection
  93. GRB 250904A: Swift-XRT refined Analysis
  94. GRB 250905A: KAIT optical upper limit
  95. GRB 250905A: Swift detection of a burst
  96. Swift GRB250905.09: Global MASTER-Net observations report
  97. Swift GRB 250904A: Global MASTER-Net observations report
  98. GRB 250904A: Enhanced Swift-XRT position
  99. GRB 250904A: TRT optical counterpart detection
  100. GRB 250904A: Prompt enhanced Swift-XRT position

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