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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"

19662 results found.

  1. GRB 140104B: Swift-XRT refined Analysis
  2. IPN triangulation of a bright burst from SGR 1935+2154
  3. GRB 210119A (Swift J1851.2-6148): Swift-BAT refined analysis
  4. GECAM detection of a short GRB 210119A or a new SGR candidate Swift J1851.2-6148
  5. GRB 210119A: Insight-HXMT/HE detection
  6. GRB 210119A: Fermi GBM observation
  7. GRB 210112A: Insight-HXMT/HE detection
  8. Short Fermi GRB 210119A or new SGR Swift J1851.2-6148: Possible MASTER Short OT detection
  9. Swift detection of a new SGR Swift J1851.2-6148 or a short GRB 210119A
  10. GRB 210112A: Deep CAHA 2.2m detection
  11. GRB 210104A: Late-time CAHA 2.2m detection
  12. Konus-Wind detection of GRB 210112A
  13. ZTF21aaeyldq (AT2021any): Detection of X-ray Emission with Swift/XRT
  14. GRB 210104A: JCMT SCUBA-2 sub-mm observations
  15. GRB 210112A: Swift/UVOT Detection
  16. GRB 210112A: 1.3m DFOT Optical upper limit
  17. GRB 210104A: AstroSat CZTI detection
  18. GRB 210112A: Swift-BAT refined analysis
  19. GRB 210112A: Swift-XRT refined Analysis
  20. GRB 210112A: AGILE detection
  21. GRB 210112A: Kitab a optical upper limit
  22. GRB 210112A: Enhanced Swift-XRT position
  23. GRB 210112A: Swift detection of a burst with an optical counterpart
  24. Correction to GCN 29278: GRB 201216C XRT refined analysis
  25. GRB 201216C: Swift-XRT refined Analysis
  26. GRB 201227A: ASIM observation
  27. GRB 210104A: SARA-KP 0.9m Optical Afterglow Detection
  28. GRB 210102B: further Swift-XRT observations
  29. GRB 210104A: CALET Gamma-Ray Burst Monitor detection
  30. GRB 210104B: Swift-BAT refined analysis
  31. GRB 210104A: early ATLAS detections of the bright afterglow
  32. GRB 210104A: Swift-XRT refined Analysis
  33. GRB 210104B: Swift/UVOT Upper Limits
  34. Konus-Wind detection of GRB 210104A
  35. GRB 210104A: 1.3m DFOT Optical Afterglow Detection
  36. GRB 210104B: Swift-XRT refined Analysis
  37. GRB 210104B: Enhanced Swift-XRT position
  38. GRB 210104A: Swift-BAT refined analysis
  39. GRB 210104B: Nanshan/NEXT optical upper limit
  40. GRB 210104B: BOOTES network optical upper limit
  41. GRB 210104A: MASTER OT rebrightening detection
  42. GRB 210104A: Swift/UVOT Detection
  43. GRB 210104A: Fermi GBM detection
  44. GRB 210104A: Enhanced Swift-XRT position
  45. GRB 210102B: Tiled Swift observations
  46. GRB 210104B: Swift detection of a burst
  47. Swift GRB210104.88: Global MASTER-Net observations report
  48. GRB 210104A: MITSuME Ishigaki optical observation
  49. GRB 210104A: MITSuME Akeno optical observation
  50. GRB 210104A: BOOTES-4/MET early optical afterglow detection
  51. GRB 210104A: Swift detection of a burst with a bright optical counterpart
  52. GRB 210102C: Swift-BAT refined analysis
  53. GRB 210102B: Swift-XRT observations
  54. GRB 210102C: Fermi GBM detection
  55. Swift GRB 210102C: Global MASTER-Net observations report
  56. GRB 210102C: Swift detection of a burst
  57. GRB 210102B: Tiled Swift observations
  58. Swift Trigger 1015615 is not a GRB
  59. Swift GRB210102.01: Global MASTER-Net observations report
  60. GRB 201229A: Swift/UVOT Detection
  61. GRB 201227A: GRAWITA VST-ESO PARANAL observations
  62. GRB 201229A: SAO RAS optical observations
  63. GRB 201229A: Nanshan/NEXT optical upper limit
  64. GRB 201227A: Swift-XRT observations
  65. GRB 201223A: SVOM-GWAC detected the optical counterpart during prompt emission phase
  66. GRB 201229A: Swift-XRT refined Analysis
  67. GRB 201229A: Swift-BAT refined analysis
  68. GRB 201229A: Enhanced Swift-XRT position
  69. GRB 201229A: Swift detection of a burst with a possible optical counterpart
  70. GRB 201227A: Tiled Swift observations
  71. GRB 201227A: Swift ToO observations
  72. IPN triangulation of GRB 201227A (short)
  73. GRB 201223A: AROMA-N Optical Observation
  74. GRB 201223A: Swift/UVOT Detection
  75. GRB 201223A: HCT optical upper limit
  76. GRB 201223A: 1.3m DFOT and 1.04m ST optical observations
  77. GRB 201223A: Swift-XRT refined Analysis
  78. GRB 201223A: Enhanced Swift-XRT position
  79. GRB 201223A: GROWTH-India Telescope (GIT) photometric follow-up.
  80. GRB 201223A: MITSuME Akeno optical observation
  81. GRB 201223A: Swift-BAT refined analysis
  82. GRB 201223A: Fermi GBM Detection
  83. GRB 201223A: BOOTES-4/MET early optical observation
  84. GRB 201223A: Nanshan/NEXT early optical afterglow detection
  85. GRB 201223A: Swift detection of a burst with a bright optical counterpart
  86. Swift GRB201223.75: Global MASTER-Net OT detection
  87. Swift GRB201223.75: Global MASTER-Net observations report
  88. Swift-XRT observations of Icecube 201222A
  89. GRB 201221A: Konus-Wind detection and joint Konus-Wind + Swift-BAT spectral analysis
  90. GRB 201221D: MMT MMIRS detection of marginally extended source
  91. GRB 201221D: LCOGT upper limits
  92. GRB 201221D: Fermi GBM detection
  93. GRB 201221D: Swift-BAT refined analysis
  94. Swift Trigger 1014012 (possible GRB 201221C) is likely not an astrophysical event
  95. GRB 201216A - further Swift-XRT observations
  96. Konus-Wind detection of GRB 201221D (short)
  97. GRB 201221D: Swift/UVOT Upper Limits
  98. GRB 201221D: Lowell Discovery Telescope afterglow observations
  99. GRB 201221D: FRAM-ORM optical limit
  100. GRB 201221D: Swift-XRT refined Analysis

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