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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

3050 results found.

  1. GRB 161004A: Swift-XRT refined Analysis
  2. GRB 161001A: Swift-XRT refined Analysis
  3. GRB 160927A: Swift-XRT refined Analysis
  4. XRT refined analysis for GRB 160925A
  5. GRB 160917A: Swift-XRT refined Analysis
  6. GRB 160912A: Swift-XRT refined Analysis
  7. GRB 160910A: Swift-XRT afterglow detection
  8. GRB 160910A: Fermi-LAT detection
  9. GRB 160905A: Swift-XRT refined Analysis
  10. GRB 160829A: Swift-XRT observations
  11. Swift trigger 710022 is not astrophysical
  12. GRB 160825A: not localized by Swift
  13. GRB 160826A: Swift-XRT refined Analysis
  14. GRB 160824A: Swift-XRT refined Analysis
  15. GRB 160821B: Swift-XRT refined Analysis
  16. GRB 160816A: Swift-XRT afterglow detection
  17. GRB 160815A: Swift-XRT refined Analysis
  18. Swift Trigger 707517 is not an astrophysical event
  19. GRB 160804A: Swift-XRT refined Analysis
  20. GRB 160801A: Swift-XRT refined Analysis
  21. Swift follow up of IceCube-160731A
  22. GRB 160714A: Swift/UVOT Upper Limits
  23. GRB 160716A: Swift-XRT refined Analysis
  24. GRB 160714A: Swift-XRT observations
  25. GRB 160714A: Swift-XRT observations
  26. GRB 160712A: Swift-XRT refined Analysis
  27. GRB 160709A: Swift-XRT observations
  28. GRB 160705B: Swift-XRT refined Analysis
  29. GRB 160703A: Swift-XRT afterglow detection
  30. GRB 160629A: Swift-XRT afterglow detection
  31. GRB 160630A: Swift-XRT refined Analysis
  32. GRB 160625A: Swift-XRT refined Analysis
  33. GRB 160625B: Fermi-LAT refined analysis
  34. GRB 160625B: Swift-XRT afterglow detection
  35. GRB 160624A: Swift-XRT refined Analysis
  36. Swift detection of a dust-scattered halo around GRB 160623A
  37. GRB 160623A: Swift-XRT afterglow detection
  38. GRB 160623A / Galactic transient: Fermi-LAT detection
  39. SGR 1617-5103 (BAT trigger 700791): Enhanced Swift-XRT position.
  40. BAT trigger 700791 (possible GRB 160622A) is SNR RCW 103
  41. GRB 160612A: Swift-XRT observations
  42. GRB 160611A: Swift-XRT refined Analysis
  43. GRB 160607A: Swift-XRT refined Analysis
  44. GRB160601A: Kanata Telescope I- and Ks-bands upper limits
  45. GRB 160601A: Swift-XRT refined Analysis
  46. GRB 160601A: MITSuME Okayama Ks-band upper-limit
  47. GRB 160530A: Swift follow-up and X-ray afterglow candidate
  48. GRB 160525B: Swift-XRT refined Analysis
  49. GRB 160521B: Swift-XRT afterglow detection
  50. GRB 160525B: Prompt enhanced Swift-XRT position
  51. GRB 160521B: Swift-XRT observations
  52. GRB 160509A: Swift-XRT afterglow detection
  53. GRB 160506A: IRSF upper limits
  54. GRB 160506A: Swift-XRT refined Analysis
  55. GRB 160504A: Swift-XRT refined Analysis
  56. GRB 160503A: Fermi-LAT detection
  57. GRB 160501A: Swift-XRT refined Analysis
  58. GRB 160422A: XRT Afterglow Confirmation
  59. GRB 160425A: Swift-XRT refined Analysis
  60. GRB 160422A: Swift-XRT afterglow detection
  61. GRB 160417A: Swift-XRT refined Analysis
  62. GRB 160409A: Swift-XRT observations
  63. GRB 160409A found in Swift BAT ground analysis
  64. GRB 160412A: Swift-XRT refined Analysis
  65. GRB 160411A: Swift-XRT refined Analysis
  66. GRB 160410A: Swift-XRT refined Analysis
  67. GRB 160408A: Swift-XRT refined Analysis
  68. GRB 160401A: Swift-XRT observations
  69. GRB 160327A: Swift-XRT refined Analysis
  70. GRB 160325A: Swift-XRT refined Analysis
  71. GRB 160321A: Swift-XRT refined Analysis
  72. GRB 160310A: A further Swift-XRT observation, no afterglow detected
  73. GRB 160314A: Swift-XRT refined Analysis
  74. GRB 160313A: Swift-XRT refined Analysis
  75. GRB 160310A: Swift-XRT observations
  76. GRB 160303A: Swift-XRT refined Analysis
  77. GRB 160228A: Swift-XRT refined Analysis
  78. GRB 160227A: Swift-XRT refined Analysis
  79. GRB 160225A: Swift-XRT refined Analysis
  80. GRB 160225A: WHT LIRIS observations
  81. GRB 160223A: Swift-XRT afterglow detection
  82. GRB 160221A: Swift-XRT afterglow detection
  83. GRB 160223B: Swift-XRT observations
  84. GRB 160221A: Swift-XRT observations
  85. GRB 160220A: nIR observations at AAT
  86. GRB 160220A: Swift-XRT refined Analysis
  87. GRB160220B: Swift/UVOT observations
  88. GRB 160220B: Swift-XRT refined Analysis
  89. GRB160220A: Swift/UVOT observations
  90. GRB 160216A: Swift-XRT refined Analysis
  91. GRB 160206A: Swift/UVOT observations
  92. GRB 160206A: Swift-XRT observations
  93. GRB 160203A: Swift-XRT refined Analysis
  94. GRB 160131A: Swift-XRT refined Analysis
  95. GRB 160127A: Swift-XRT refined Analysis
  96. GRB 160123A: Swift-XRT refined Analysis
  97. GRB 160121A: Swift-XRT refined Analysis
  98. GRB 160117A: Swift-XRT afterglow detection
  99. GRB 160119A: Swift-XRT refined Analysis
  100. GRB 160117A: Swift/UVOT Upper Limits

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