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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"

19662 results found.

  1. GRB 181002A: Swift-XRT refined Analysis
  2. GRB 181003A: LCO Cerro Tololo observations
  3. GRB 181003A: MASTER optical observation
  4. GRB181002A: GOTO optical limits
  5. GRB 181002A: Swift/UVOT Upper Limits
  6. GRB 181003A: Swift-XRT observations
  7. GRB 181003A: Swift detection of a burst
  8. GRB 181002A: Swift-BAT refined analysis
  9. GRB 181002A: MASTER optical observation
  10. GRB 181002A: Enhanced Swift-XRT position
  11. Konus-Wind observation of GRB 180925A
  12. GRB 181002A: Swift detection of a burst
  13. Trigger 864882: Swift detection of Crab in its normal state
  14. GRB 180930A: Swift-BAT refined analysis
  15. GRB 180930A: Swift-XRT refined Analysis
  16. GRB 180930A: Swift/UVOT Upper Limits
  17. GRB 180930A: Enhanced Swift-XRT position
  18. GRB 180930A: KAIT Optical Upper Limit
  19. GRB 180930A: Prompt enhanced Swift-XRT position
  20. GRB 180930A: Swift detection of a burst
  21. GRB 180924A: Swift/UVOT Upper Limits
  22. GRB 180925A: Insight-HXMT/HE detection
  23. GRB 180925A: Swift/UVOT Detection
  24. GRB 180925A: Swift-BAT refined analysis
  25. GRB 180925A: Swift-XRT refined Analysis
  26. GRB 180925A: Enhanced Swift-XRT position
  27. GRB 180925A: Prompt enhanced Swift-XRT position
  28. GRB 180925A: Swift detection of a burst
  29. GRB 180924A: MASTER inspection
  30. GRB 180924A: Swift-XRT refined Analysis
  31. GRB 180924A: Swift-BAT refined analysis
  32. GRB 180924A: Enhanced Swift-XRT position
  33. GRB 180924A: Swift detection of a burst
  34. Swift Trigger 863053 is not an astrophysical event
  35. GRB180914B: Swift UVOT position correction to circ. 23241
  36. GRB 180914B: AstroSat CZTI detection
  37. GRB 180914A: AstroSat CZTI detection
  38. GRB 180914B: AGILE/MCAL refined analysis
  39. GRB180914B: Swift UVOT detection of an optical afterglow
  40. GRB 180914B: RATIR Optical and NIR Observations
  41. GRB 180914B: KAIT Optical Afterglow Candidate
  42. GRB 180914B: Swift-XRT afterglow detection
  43. GRB 180914A: RATIR Optical and NIR Observations
  44. GRB 180914B: Tiled Swift observations
  45. GRB 180914B: Fermi-LAT detection
  46. GRB 180914A: Swift-XRT observations
  47. GRB 180914A: Tiled Swift observations
  48. GRB 180914A: Fermi-LAT detection
  49. GRB 180905A: Swift/UVOT Upper Limits
  50. GRB 180905A, Swift-BAT refined analysis
  51. GRB 180905A: RATIR Optical and NIR Observations
  52. GRB 180905A: Swift-XRT refined Analysis
  53. GRB 180904A: BOOTES-2/TELMA early observations
  54. GRB 180905A: BOOTES-3/YA optical observations
  55. GRB 180905A: Enhanced Swift-XRT position
  56. GRB 180904A: AbAO optical upper limit
  57. GRB 180904A: Swift/UVOT Upper Limits
  58. GRB 180904A: Swift-BAT refined analysis
  59. GRB 180905A: Swift detection of a burst
  60. GRB 180904A: Swift-XRT refined Analysis
  61. GRB 180904A: LT early observations
  62. GRB 180904A: SAO RAS optical observations
  63. GRB 180904A: OSN observations
  64. GRB 180904A: Enhanced Swift-XRT position
  65. GRB 180904A: Swift detection of a burst
  66. Konus-Wind observation of GRB 180828A
  67. GRB 180829A: Swift-XRT observations
  68. GRB 180828A: AstroSat CZTI detection
  69. GRB 180828A: Swift/UVOT Upper Limits
  70. GRB 180828A: RATIR Optical and NIR Observations
  71. GRB 180828A: Swift-BAT refined analysis
  72. GRB 180829A: Tiled Swift observations
  73. GRB 180828A: Swift-XRT refined Analysis
  74. GRB 180828A / Swift J1754.9-2548: Enhanced Swift-XRT position
  75. GRB 180828A: Fermi GBM observation
  76. GRB 180828A: Swift detection of a GRB or possible Galactic Transient Swift J1754.9-2548
  77. GRB 180818B: TSHAO optical upper limit
  78. GRB 180823A, Swift-BAT refined analysis
  79. IPN Triangulation of GRB 180824A (short)
  80. GRB 180823A: Swift/UVOT Upper Limits
  81. GRB 180823A: RATIR Optical and NIR Observations
  82. GRB 180823A: Swift-XRT refined Analysis
  83. GRB 180823A: Enhanced Swift-XRT position
  84. GRB 180823A: Swift detection of a burst
  85. GRB 180821A: VLT observations
  86. GRB 180821A: Swift/UVOT Upper Limits
  87. GRB 180821A: Swift-BAT refined analysis
  88. GRB 180821A: iTelescope counterpart is not the afterglow
  89. GRB 180821A: Swift-XRT refined Analysis
  90. GRB 180821A: LCO Siding Springs observations
  91. GRB 180821A: Enhanced Swift-XRT position
  92. GRB 180818B: 1.5m OSN optical afterglow candidate
  93. GRB 180821A: iTelescope optical afterglow detection
  94. GRB 180821A: BOOTES-3/YA optical observations
  95. GRB 180821A: Swift detection of a burst
  96. GRB180806A: confirmation of the X-ray afterglow
  97. GRB 180818B: Swift-XRT refined Analysis
  98. GRB 180818B: Swift-BAT refined analysis
  99. GRB 180818A: Swift-BAT refined analysis
  100. GRB 180818B: Fermi GBM observations

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