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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"

18435 results found.

  1. GRB 120922A: GROND afterglow candidate
  2. GRB 120922A: Prompt enhanced Swift-XRT position
  3. GRB 120922A: Swift detection of a burst
  4. GRB 120919A: Swift/UVOT Upper Limits
  5. GRB 120919A: Swift-XRT observations
  6. GRB 120918A: Swift-BAT refined analysis
  7. Swift trigger 534017 was not an astrophysical event
  8. Swift Trigger 534017 is probably not real.
  9. GRB 120918A: Swift detection of a burst
  10. IPN Triangulation of long GRB 120916A
  11. Swift Transient Swift J174510.8-262411: Swift-BAT refined analysis
  12. Swift Trigger 533836 is a new Galactic transient
  13. GRB 120913B: Fermi GBM observation
  14. GRB 120913B: Swift-BAT refined analysis
  15. GRB 120913A: Fermi GBM observation
  16. GRB 120913B: FRAM early follow up and detection
  17. GRB 120913A: Swift-BAT refined analysis
  18. Continued Skynet/PROMPT observations of GRB120913B
  19. GRB 120913B: TAROT La Silla observatory optical detection
  20. Skynet/PROMPT observations of GRB120913B
  21. GRB 120913B: Swift detection of a burst
  22. GRB 120913A: Swift detection of a burst
  23. GRB 120911A: optical upper limit CrAO
  24. GRB 120911A: optical upper limit ISON-NM
  25. GRB 120911A: Fermi GBM observation
  26. GRB 120911A: Fermi/LAT upper limit
  27. GRB 120911A: Swift/UVOT Upper Limits
  28. GRB 120911A: Swift-XRT refined Analysis
  29. GRB 120911A: Swift-BAT refined analysis
  30. GRB 120911A: Enhanced Swift-XRT position
  31. GRB 120911A: Swift-XRT observations
  32. GRB 120911A: ROTSE-III Optical Limits
  33. GRB 120911A: Swift detection of a burst
  34. GRB 120907A: SMA upper limits
  35. GRB 120908A and GRB 120909A : Fermi/LAT upper limit
  36. GRB 120908A: Swift Observations
  37. GRB 120909A: TAROT La Silla observatory optical observations
  38. GRB 120909A: Pi of the Sky upper limits
  39. GRB 120909A: Fermi GBM observation
  40. Konus-Wind observation of GRB 120909A
  41. GRB 120909A: Swift/UVOT Detection
  42. GRB 120909A: Swift-XRT refined Analysis
  43. GRB 120909A: Swift-BAT refined analysis
  44. GRB 120909A: Enhanced Swift-XRT position
  45. GRB 120909A: GROND detection of the afterglow
  46. Skynet/PROMPT Observations of GRB120909A
  47. GRB 120909A: Swift detection of a burst
  48. GRB 120907A: EVLA observations
  49. GRB 120907A: Swift/UVOT Detection
  50. GRB 120907A: Swift-XRT refined Analysis
  51. GRB 120907A: Enhanced Swift-XRT position
  52. GRB 120907A: Fermi GBM detection
  53. GRB 120907A: Swift-BAT refined analysis
  54. GRB 120907A: NOT optical observations
  55. GRB 120907A MASTER optical observations
  56. GRB 120907A: ROTSE-III Optical Limits
  57. GRB 120907A: Swift detection of a burst with optical counterpart
  58. XMM observations of the short GRB120804A
  59. GRB 120830A: Further Swift Observations
  60. GRB 120830A: catalog source at Uvot position
  61. GRB 120830A: Swift-XRT and UVOT observations
  62. IPN Triangulation of short GRB 120830A
  63. GRB 120830A: Fermi-LAT detection of a short burst
  64. GRB 120819A: Swift/UVOT Upper Limits
  65. GRB 120817A: Swift/UVOT Upper Limits
  66. GRB 120821A: Swift/XRT observations
  67. GRB 120821A: Swift/UVOT Upper Limits
  68. GRB 120821A: GROND upper limits
  69. GRB 120817B - PTF Observations
  70. GRB 120817A: RAPTOR Limits During Gamma-Ray Emitting Interval
  71. GRB 120817B: BAT location in ground analysis and refined analysis
  72. GRB 120819A: Bassano Bresciano Observatory optical observations
  73. GRB 120819A: Swift-BAT refined analysis
  74. GRB 120819A: GROND afterglow confirmation
  75. GRB 120819A: Swift-XRT refined Analysis
  76. GRB 120819A: Enhanced Swift-XRT position
  77. GRB 120819A: MASTER optical observations
  78. GRB 120819A: Swift detection of a burst
  79. GRB 120817B: Swift-XRT observations
  80. GRB 120816A: Swift/UVOT Detection of the Optical Afterglow
  81. GRB 120815A: MASTER-ICATE observations
  82. IPN Triangulation of GRB 120816B (short/exceptionally intense)
  83. GRB 120817A: Swift-XRT refined Analysis
  84. IPN Triangulation of GRB 120817B (short/very intense)
  85. GRB 120817A: Swift-BAT refined analysis
  86. GRB 120816A: optical upper limit
  87. GRB 120817A: Enhanced Swift-XRT position
  88. GRB 120815A: Swift/UVOT Detection of the Optical Afterglow
  89. GRB 120816A: Bassano Bresciano Observatory optical observations
  90. GRB 120816A: Swift-XRT refined Analysis
  91. GRB 120817A: Swift-XRT observations
  92. GRB 120817A: Swift detection of a burst
  93. GRB 120816A: Enhanced Swift-XRT position
  94. GRB 120816A: Swift-BAT refined analysis
  95. GRB 120816A: TAROT Calern observatory optical observations
  96. GRB 120816A: ROTSE-III Optical Limits
  97. GRB 120816A: Swift detection of a burst
  98. GRB 120815A: Swift-XRT refined Analysis
  99. GRB 120815A: Swift-BAT refined analysis
  100. GRB 120815A: Enhanced Swift-XRT position

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