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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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

21525 results found.

  1. GRB 211226A: Swift/BAT-GUANO detection outside the coded FOV
  2. GRB 211225B: Swift-BAT refined analysis
  3. Swift GRB 211225B: Global MASTER-Net observations report
  4. GRB 211225B: Swift detection of a burst
  5. GRB 211211A: observations with the 3.6m Devasthal Optical Telescope
  6. GRB 211223C: Swift-BAT refined analysis
  7. GRB 211223C: BOOTES-4/MET optical upper limit
  8. Swift GRB 211223C: Global MASTER-Net observations report
  9. Fermi GBM Sub-Threshold Detection of GRB 211221A
  10. Fermi GBM Sub-Threshold Detection of GRB 211207A
  11. GRB 211221A: Swift-BAT refined analysis
  12. GRB 211223C: Swift detection of a burst
  13. GRB 211221A: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  14. GRB 211219A: AstroSat CZTI detection
  15. GRB 211221A: Swift-XRT refined Analysis
  16. GRB 211221A: BOOTES-4/MET optical upper limit
  17. GRB 211221A: MeerLICHT optical limits
  18. GRB 211221A: NOT optical limits
  19. GRB 211221A: Enhanced Swift-XRT position
  20. Swift GRB 211221A: Global MASTER-Net observations report
  21. GRB 211221A: Swift detection of a burst
  22. GRB 211219A: Swift/BAT-GUANO detection outside the coded FOV
  23. GRB 211216A: Fermi GBM observation
  24. GRB 211106A: XMM-Newton monitoring campaign detections
  25. GRB 211216A: Swift/BAT-GUANO detection outside the coded FOV
  26. GRB 211211A: Insight-HXMT/HE detection
  27. GRB 211211A: Very fast decay observed from CAFOS/2.2mCAHA
  28. GRB 211211A: HCT and GIT optical follow up observations
  29. GRB 211211A: CALET Gamma-Ray Burst Monitor detection
  30. GRB 211211A: Swift/UVOT detection
  31. GRB 211211A: NOT optical spectroscopy
  32. Swift GRB 211211A: Global MASTER-Net observations report
  33. GRB 211211A: LCO Optical Observations
  34. GRB 211211A: Nanshan/NEXT optical observations
  35. GRB 211211A: Swift-XRT refined Analysis
  36. GRB 211211A: Fermi GBM observation
  37. GRB 211211A: Swift-BAT refined analysis
  38. GRB 211211A: Enhanced Swift-XRT position
  39. GRB 211207A: Swift/UVOT Detection
  40. GRB 211211A: KAIT Optical Afterglow Candidate
  41. GRB 211211A: Swift detection of a bright burst
  42. GRB 211207A: Swift-BAT refined analysis
  43. GRB 211204C: Fermi GBM detection
  44. GRB 211207A: Swift-XRT refined Analysis
  45. GRB 211207A: Enhanced Swift-XRT position
  46. Swift GRB 211207A: Global MASTER-Net observations report
  47. GRB 211207A: Swift detection of a burst with an optical counterpart
  48. GRB 211206A: AstroSat CZTI detection
  49. GRB 211204C: AstroSat CZTI detection
  50. IPN triangulation of GRB 211204C
  51. GRB 211206A: Swift/BAT-GUANO detection outside the coded FOV
  52. GRB 211204C: Swift/BAT-GUANO detection outside the coded FOV
  53. GRB 211124A: Fermi GBM Observation
  54. Swift Trigger 1086826 (possible GRB 211203A) is likely not an astrophysical event
  55. Swift GRB 211203A: Global MASTER-Net observations report
  56. Fermi GBM Upper limits for GRB 211203A
  57. GRB 211203A: Swift detection of a burst
  58. GRB 211201A: Swift/BAT-GUANO detection likely outside the coded FOV
  59. GRB 211106A: GECAM detection
  60. GRB 211129A: Swift-BAT refined analysis
  61. GRB 211129A: Swift-XRT refined Analysis
  62. GRB 211129A: Swift/UVOT Upper Limits
  63. GRB 211106A: Chandra Observations
  64. GRB 211129A: Fermi GBM observation
  65. Swift GRB 211129A: Global MASTER-Net observations report
  66. GRB 211129A: Nanshan/NEXT optical upper limit
  67. GRB 211129A: Enhanced Swift-XRT position
  68. IPN triangulation of GRB 211118A
  69. GRB 211129A: MITSuME Akeno optical upper limits
  70. GRB 211129A: Swift detection of a burst
  71. GRB 211120548: Fermi GBM observation
  72. Chandra observations of GRB 210905A
  73. GRB 211118A: Fermi GBM detection
  74. IPN triangulation of GRB 211124A (short)
  75. GRB 211124A: Swift/BAT-GUANO detection of a short burst outside the coded FOV
  76. Trigger_21473: Tiled Swift observations
  77. GRB 211023B: LBT likely spectroscopic redshift of the host galaxy
  78. GRB 211120B: Swift/BAT-GUANO detection outside the coded FOV
  79. GRB 211118A: AstroSat CZTI detection
  80. GRB211118A: Swift/BAT-GUANO detection outside the coded FOV
  81. Konus-Wind detection of GRB 211107B
  82. GRB 211106A: Swift/UVOT upper limits
  83. IPN triangulation of GRB 211106A (short)
  84. Short GRB 211106A: spectroscopy of galaxies in the field
  85. GRB 211107B: Swift-XRT afterglow detection
  86. GRB 211106A: VLT/FORS2 optical observations
  87. GRB 211106A, GROND observations
  88. GRB 211106A: Swift-XRT afterglow detection
  89. GRB 211107B: Swift-XRT observations
  90. MeerLICHT follow-up of GRB 211106A
  91. GRB 211107B: Swift ToO observations
  92. GRB 211107B: Swift/BAT detection
  93. Fermi GBM Sub-Threshold Detection of GRB 211106A
  94. Konus-Wind detection of GRB 211106A
  95. GRB 211106A: Swift-XRT observations
  96. GRB 211106A: Swift ToO observations
  97. GRB 211106A: Swift/BAT-GUANO candidate arcminute localization of a short burst
  98. GRB 211105A: Swift/BAT-GUANO detection outside the coded FOV
  99. Swift Trigger 1082569 is probably not a GRB
  100. GRB 211024A: MITSuME Akeno optical observation

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