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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"

26125 results found.

  1. GRB 210606A: Swift ToO observations
  2. Fermi GRB 210606A: DDOTI Upper Limits on the Afterglow
  3. GRB 210606A: Swift/BAT-GUANO detection and arcminute localization
  4. GRB 210605B: Swift ToO observations
  5. GRB 210605B: Swift/BAT-GUANO detection and arcminute localization
  6. Initial results of a NICER X-ray monitoring of the magnetar, Swift J1555.2-5402
  7. Fermi GBM Sub-Threshold Detection of new Swift SGR J1555.2-5402
  8. SGR J1555.2-5402: Swift-BAT refined analysis
  9. Swift J1555.2-5402: Swift XRT refined analysis of the new SGR
  10. NICER discovery of 3.86 s pulsations from a new magnetar: SGR J1555.2-5402
  11. Swift Detection of probable new Swift SGR J1555.2-5402
  12. Swift GRB210603.41: Global MASTER-Net observations report
  13. GRB 210529B: DDOTI Upper Limits on the Afterglow
  14. GRB 210528B: DDOTI Upper Limits on the Afterglow
  15. GRB 210527A: Swift-BAT refined analysis
  16. GRB 210527A: Swift/UVOT Observations
  17. GRB 210527A: GIT optical upper limit
  18. GRB 210527A: MITSuME Akeno optical upper limits
  19. Swift GRB 210527A: Global MASTER-Net observations report
  20. GRB 210527A: Swift-XRT refined Analysis
  21. GRB 210527A: RATIR Optical and NIR Observations
  22. GRB 210527A: Enhanced Swift-XRT position
  23. GRB 210527A: Swift-XRT observations
  24. GRB 210527A: Swift detection of a burst
  25. GRB 210306A: LBT observations of the likely host galaxy
  26. ZTF21aayokph (AT2021lfa): LBT optical observations
  27. Fermi GRB 210524B: DDOTI Upper Limits on the Afterglow
  28. IPN triangulation of GRB 210524A
  29. GRB 210520A: Swift-XRT observations
  30. GRB210413B: further Swift-XRT observations
  31. GRB 210520A: Tiled Swift observations
  32. GRB 210520A: Fermi-LAT detection
  33. GRB 210517A: KCT optical upper limit
  34. GRB 210518.889: DDOTI Upper Limits on the Afterglow
  35. Konus-Wind detection of GRB 210514A
  36. GRB 210517A: Swift-BAT refined analysis
  37. GRB 210517A: Swift-XRT refined Analysis
  38. GRB 210517A: Swift/UVOT Upper Limits
  39. GRB 210515C: Swift/UVOT Upper Limits
  40. GRB 210517A: VLT/X-shooter optical afterglow and redshift
  41. GRB 210517A: AGILE detection
  42. GRB 210514A: CALET Gamma-Ray Burst Monitor detection
  43. GRB 210517A: Enhanced Swift-XRT position
  44. Swift GRB 210517A: Global MASTER-Net observations report
  45. GRB 210517A: Swift detection of a burst
  46. GRB 210515C: LCO Optical Upper Limit
  47. GRB 210504A: LCO Optical Afterglow Detection
  48. GRB 210514A: Swift/UVOT Upper Limits
  49. GRB 210515C: Swift-XRT refined Analysis
  50. Swift GRB210515.83: Global MASTER-Net observations report
  51. GRB 210515C: Swift-BAT refined analysis
  52. GRB 210515C: Swift detection of a burst
  53. GRB 210514A: Swift-BAT refined analysis
  54. Swift GRB210514.71: Global MASTER-Net observations report
  55. GRB 210514A: Swift XRT light curve is fading
  56. GRB 210514A: Swift-XRT refined Analysis
  57. GRB 210514A: Enhanced Swift-XRT position
  58. GRB 210514A: update on the BAT trigger time and burst duration
  59. GRB 210514A: Swift detection of a burst
  60. GRB 210512.786: DDOTI Upper Limits on the Afterglow
  61. GRB210510A: Optical afterglow candidate from the Zwicky Transient Facility
  62. Short GRB 210323A: likely host galaxy detection
  63. GRB 210511B: DDOTI Upper Limits on the Afterglow
  64. IPN triangulation of GRB 210427A
  65. Fermi GRB 210510A: DDOTI Upper Limits on the Afterglow
  66. GRB 201228B: Swift/BAT-GUANO archival detection and arcminute localization
  67. GRB 200716A: Swift/BAT-GUANO archival detection and arcminute localization
  68. Swift trigger 1047857 is 4U 1700-377
  69. GRB 210509A: RATIR Optical and NIR Upper Limits
  70. GRB 210509A: Swift/UVOT Upper Limits
  71. GRB 210509A: Swift-XRT refined Analysis
  72. GRB 210509A: Swift-BAT refined analysis
  73. Swift GRB 210509A: Global MASTER-Net observations report
  74. GRB 210509A: Enhanced Swift-XRT position
  75. GRB 210509A: BOOTES-4/MET optical upper limit
  76. GRB 210509A: Swift-XRT observations
  77. GRB 210509A: Swift detection of a burst
  78. GRB 210506A: Swift/BAT-GUANO position retraction
  79. IPN triangulation of GRB 210506A
  80. GRB 210506A: Swift-XRT observations
  81. GRB 210506A: Nanshan/NEXT optical upper limit
  82. GRB 210506A: TNG NIR upper limits
  83. ZTF21aayokph (AT2021lfa): X-ray Detection with Swift/XRT
  84. GRB 210506A: Swift ToO observations
  85. GRB 210506A: Swift/BAT-GUANO detection and possible arcminute localization of a short hard burst
  86. GRB 210504A: Lowell Discovery Telescope optical observations
  87. ZTF21aayokph (AT2021lfa): Redshift from Gemini South
  88. GRB 210504A: VLT X-shooter redshift
  89. GRB 210504A: Swift-XRT refined Analysis
  90. GRB 210504A: Swift-BAT refined analysis
  91. ZTF and LT observations of ZTF21aayokph (AT2021lfa), a fast-fading red transient
  92. GRB 210504A: NOT optical afterglow detection
  93. GRB 210504A: MITSuME Akeno optical upper limits
  94. Fermi GRB 210503A: DDOTI Upper Limits on the Afterglow
  95. GRB 210504A: AST3-3 YaoAn Optical Upper Limit
  96. GRB 210504A: Swift/UVOT Detection
  97. GRB 210504A: BOOTES-4/MET optical upper limit
  98. Swift GRB210504.58: Global MASTER-Net observations report
  99. GRB 210504A: update on the BAT trigger time and burst duration
  100. GRB 210504A: Swift detection of a burst

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