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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"

19666 results found.

  1. GRB 180818B: Swift-XRT refined Analysis
  2. GRB 180818B: Swift-BAT refined analysis
  3. GRB 180818A: Swift-BAT refined analysis
  4. GRB 180818B: Fermi GBM observations
  5. GRB 180818B: Swift/UVOT Upper Limits
  6. GRB 180818B: Enhanced Swift-XRT position
  7. GRB 180818A: Swift/UVOT Upper Limits
  8. GRB 180818B: Swift detection of a burst
  9. GRB 180818A: Swift-XRT refined Analysis
  10. GRB 180818A: Enhanced Swift-XRT position
  11. GRB 180818A: Swift detection of a burst
  12. Swift Trigger 853790 is probably not an astrophysical source
  13. GRB 180809B: AstroSat CZTI detection
  14. GRB 180809A: further Swift/XRT observations
  15. GRB 180812A: Swift/UVOT Detection
  16. GRB 180812A: Swift-BAT refined analysis
  17. GRB 180812A: Fermi GBM detection
  18. GRB 180812A: Swift-XRT refined Analysis
  19. GRB 180812A: Enhanced Swift-XRT position
  20. GRB 180812A: BOOTES-5/JGT optical afterglow detection
  21. GRB 180812A: Swift detection of a burst
  22. Konus-Wind observation of GRB 180809B
  23. GRB180809B TUG T60 observations
  24. GRB 180809B: Swift-XRT refined Analysis
  25. GRB 180809B, Swift-BAT refined analysis
  26. Swift Trigger 852625: Swift/BAT/XRT/UVOT observations
  27. GRB 180809B: Swift/UVOT Detection
  28. GRB 180809A: Fermi GBM observation
  29. GRB 180809B: CALET Gamma-Ray Burst Monitor detection
  30. Swift Trigger 852625: a possible GRB
  31. GRB180809B: MASTER Triple Independent Automatic OT Detection
  32. GRB 180809B: LCO Sutherland observations
  33. GRB 180809B: GROND Detection of the NIR Afterglow
  34. GRB180809B: MASTER OT observation
  35. GRB 180809A: Swift-XRT afterglow detection
  36. GRB 180809B: Swift detection of a burst with an optical afterglow
  37. GRB 180809A: Tiled Swift observations
  38. GRB 180728A: AstroSat CZTI detection
  39. GRB180806A: correction to Circular 23097
  40. GRB 180806A: Swift-XRT afterglow detection
  41. GRB 180806A: Fermi GBM detection
  42. GRB 180806A: Swift ToO observations
  43. GRB 180805B: 1.5m OSN I-band observation
  44. GRB 180805B: GOTO optical limits
  45. GRB 180805B: MASTER optical late inspection short GRB with extended emission
  46. GRB 180805A: Swift-XRT refined Analysis
  47. GRB 180805B: Swift-XRT refined Analysis
  48. GRB 180805B: Swift-BAT refined analysis (short GRB with extended emission)
  49. GRB 180805A: Swift-BAT refined analysis
  50. GRB 180805B: Swift/UVOT Upper Limits
  51. GRB 180805B: Fermi GBM detection
  52. GRB 180805B: Enhanced Swift-XRT position
  53. GRB 180805B: Swift detection of a burst
  54. GRB 180805A: Enhanced Swift-XRT position
  55. GRB 180805A: Swift detection of a burst
  56. GRB 180727A: Swift/BAT spectral lag result
  57. GRB 180728A: Swift/UVOT Detection
  58. GRB 180727A: Swift/UVOT Upper Limits
  59. Konus-Wind observation of the bright nearby GRB 180728A
  60. GRB 180715A: CALET CAL gamma-ray analysis
  61. IPN Triangulation of GRB 180728B (short)
  62. GRB 180728A: Swift-BAT refined analysis
  63. GRB 180728A: Fermi GBM observation
  64. GRB 180728A: Swift-XRT refined Analysis
  65. GRB 180728A: Enhanced Swift-XRT position
  66. GRB 180728A: MASTER OT J165415.75-540239.27 is the Optical Counterpart of GRB
  67. GRB 180728A: Swift-XRT observations
  68. GRB 180728A: MASTER OT (= new object) detection
  69. GRB 180727A: Swift-BAT refined analysis
  70. GRB 180728A: Swift detection of a bright burst
  71. GRB 180727A: Swift-XRT refined Analysis
  72. GRB 180727A: Fermi GBM observation
  73. GRB 180727A: Swift detection of a burst
  74. GRB 180720B: CALET Gamma-Ray Burst Monitor detection
  75. GRB 180720B: OAJ optical observations
  76. GRB 180720B long follow up requested
  77. GRB 180721A: KAIT Optical Upper Limit
  78. GRB 180720B: KAIT Optical Observations
  79. GRB 180722A: Swift-XRT observations
  80. GRB 180718B: Swift-XRT observations
  81. GRB 180718A: Swift-XRT observations
  82. GRB 180720B: MASTER Global Net OT observations
  83. GRB 180720B: ISON-Castelgrande optical observations
  84. GRB 180721A: BOOTES-5/JGT optical observations
  85. GRB 180720C: BOOTES-2/TELMA optical observations
  86. GRB 180722A: Tiled Swift observations
  87. GRB 180721A: Swift/UVOT Upper Limits
  88. GRB 180715A: AstroSat CZTI detection
  89. Konus-Wind observation of GRB 180720B
  90. GRB 180720C: Swift-XRT refined Analysis
  91. GRB 180721A: Swift-BAT refined analysis
  92. GRB 180720C: Swift-BAT refined analysis
  93. GRB 180721A: Swift-XRT refined Analysis
  94. GRB 180720B: Swift-BAT refined analysis
  95. GRB 180721A: Enhanced Swift-XRT position
  96. GRB 180721A: LCO Haleakala observations
  97. GRB 180721A: Swift detection of a burst
  98. GRB 180720B: MAXI/GSC detection
  99. GRB 180720C: Swift/UVOT Upper Limits
  100. GRB 180720C: LT observations

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