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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. MASTER: Optical Blazar Flare Detection during Fermi trigger 502272781 inspection
  2. GRB 161129A: POLAR Detection
  3. GRB 161202A: Astrosat CZTI detection
  4. GRB 161202A: RATIR Optical and NIR Observations
  5. GRB 161202A: Swift-BAT refined analysis
  6. GRB 161202A: Swift/UVOT Upper Limits
  7. GRB 161202A: Swift-XRT refined Analysis
  8. GRB 161202A: Fermi-LAT detection
  9. GRB 161202A: Enhanced Swift-XRT position
  10. GRB 161202A: Swift detection of a burst
  11. GRB 161129A: Swift-BAT refined analysis
  12. GRB 161129A: Fermi GBM Detection
  13. GRB 161129A: Swift/UVOT Detection
  14. GRB161129A : Astrosat CZTI detection
  15. GRB 161129A: Swift-XRT refined Analysis
  16. GRB 161129A: Enhanced Swift-XRT position
  17. GRB 161129A: Swift detection of a burst
  18. GRB 161123A: Swift-XRT observations
  19. Swift Trigger 723539 is not an astrophysical event
  20. GRB 161123A: Tiled Swift observations
  21. GRB 161108A: 15 GHz upper limits from AMI
  22. Swift Trigger 723124 is probably not a GRB
  23. GRB 161117B: Swift-XRT refined Analysis
  24. Konus-Wind observation of GRB 161117A
  25. GRB 161117A iTelescope observation
  26. GRB 161117A: MASTER-OAFA (Argentina) prompt OT observations
  27. GRB 161117A: TAROT La Silla observatory optical observations
  28. GRB 161117A: Fermi GBM detection/observation
  29. GRB 161117B: Swift/UVOT Upper Limits
  30. GRB 161117A: Swift/UVOT Detection
  31. GRB 161117B: Swift-BAT refined analysis
  32. GRB 161117A: Swift-BAT refined analysis
  33. Swift Trigger 722681 is probably not a GRB
  34. GRB 161117B: Enhanced Swift-XRT position
  35. GRB 161117A: Swift-XRT refined Analysis
  36. GRB 161117A: Enhanced Swift-XRT position
  37. GRB 161117B: LCO optical observations
  38. GRB 161117B: Swift detection of a burst
  39. GRB 161117A: Swift detection of a burst with an optical counterpart
  40. GRB 161113A: Swift-BAT refined analysis
  41. GRB 161113A: Swift/UVOT Upper Limits
  42. GRB 161113A: Swift-XRT refined Analysis
  43. GRB 161113A: Enhanced Swift-XRT position
  44. GRB 161113A: RATIR Optical and NIR Observations
  45. GRB 161113A: Swift detection of a burst
  46. GRB 161109A: Swift/UVOT Upper Limits
  47. GRB 161104A: Chandra X-ray observations
  48. GRB 161109A: Swift-XRT observations
  49. GRB 161108A: Swift/UVOT Upper Limits
  50. GRB 161109A: Tiled Swift observations
  51. GRB 161105A: Swift/UVOT Upper Limits
  52. GRB 161109A: Fermi-LAT detection
  53. GRB 161108A: TAROT Calern observatory optical observations
  54. GRB 161105A: TAROT La Silla observatory optical observations
  55. GRB 161108A, Swift-BAT refined analysis
  56. GRB 161108A: Swift-XRT refined Analysis
  57. GRB 161108A: Enhanced Swift-XRT position
  58. GRB 161108A: Swift detection of a burst
  59. GRB 161022A: 15 GHz upper limits from AMI
  60. GRB 161017A: 15 GHz upper limits from AMI
  61. GRB 161105A: Swift-XRT refined Analysis
  62. GRB 161104A: Gemini South optical observations
  63. GRB 161105A: Swift-BAT refined analysis
  64. GRB 161105A: Enhanced Swift-XRT position
  65. GRB 161105A: MASTER-IAC early optical observations
  66. GRB 161104A: GROND observations
  67. GRB 161105A: Swift detection of a burst
  68. GRB 161104A: Swift/UVOT Upper Limits
  69. GRB 161104A, Swift-BAT refined analysis
  70. GRB 161104A: Swift-XRT refined Analysis
  71. IceCube-161103: Swift-XRT observations
  72. GRB 161104A: Enhanced Swift-XRT position
  73. GRB 161104A: Swift detection of a short burst
  74. GRB 161014A: 15 GHz upper limits from AMI
  75. GRB 161023A: Swift-XRT afterglow detection
  76. GRB 161023A: Swift ToO observations
  77. Swift Trigger 718919 is not an astrophysical event.
  78. GRB 161022A: Swift-BAT refined analysis
  79. Swift Trigger 718766 is not an astrophysical event.
  80. GRB 161022A: RATIR Optical and NIR Observations
  81. GRB 161022A: Swift/UVOT Upper Limits
  82. GRB 161022A: Fermi GBM observation
  83. GRB 161022A: Enhanced Swift-XRT position
  84. GRB 161022A: Swift-XRT refined Analysis
  85. IPN Triangulation of GRB 161020B
  86. GRB 161022A: LT observations
  87. GRB 161022A: TAROT Calern observatory optical observations
  88. GRB 161022A: Prompt enhanced Swift-XRT position
  89. GRB 161022A: Swift detection of a burst
  90. GRB 161015A: further Swift-XRT follow-up observations
  91. GRB 161011A: 15 GHz upper limits from AMI
  92. GRB 161007A: 15 GHz upper limits from AMI
  93. Konus-Wind observation of GRB 161017A
  94. GRB 161017A: LT optical observations
  95. GRB161017A optical R band observations with SARA-RM
  96. GRB 161017A: GTC additional spectroscopy and refined redshift
  97. GRB 161017A: Swift-BAT refined analysis
  98. GRB 161017A: Lomonosov Gamma Ray and MASTER Optical prompt observations
  99. GRB 161017A: Swift/UVOT Detection
  100. GRB 161017A: Swift-XRT refined Analysis

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