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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"

25843 results found.

  1. GRB 081102: MASTER prompt optical limit
  2. GRB 081102: Swift-XRT refined analysis
  3. GRB 081102: Swift-BAT refined analysis
  4. GRB 081102: Enhanced Swift-XRT position
  5. Radio observation of GRB 080218b with ATCA
  6. Radio observation of GRB 080229a with ATCA
  7. GRB 081102: MASTER VWF promt observation
  8. GRB 081102: Swift detection of a burst
  9. SGR 0501+4516: optical observations in August
  10. SGR 0623-0006 or GRB 081101: Swift-XRT refined analysis
  11. SGR 0623-0006 or GRB 081101: Swift-BAT/-XRT refined analysis
  12. GRB 081024B: BTA deep optical observations
  13. GRB 081024B: new Swift-XRT observations
  14. Radio observation of GRB 080229b with ATCA
  15. GRB 081024B: VLA radio observation
  16. GRB 081029: UVOT Detection of the Optical Afterglow
  17. GRB 081029: Swift-BAT refined analysis
  18. GRB081029: Swift XRT refined analysis
  19. GRB 081025: Suzaku WAM observation of the prompt emission
  20. GRB 081029: Enhanced Swift-XRT position
  21. GRB 081028: GROND Confirmation of the Optical/NIR Afterglow
  22. GRB 081029: REM observations
  23. Radio observation of GRB 080303 with ATCA
  24. Radio observation of GRB 080411 with ATCA
  25. GRB 081029: GROND Detection of the Optical/NIR Afterglow
  26. GRB 081029: ROTSE-III Detection of Optical Counterpart
  27. GRB 081028B: Fermi GBM detection
  28. GRB 081021: Fermi GBM detection
  29. Swift UVOT observations of GRB081028
  30. GRB 081028: Swift-XRT refined analysis
  31. GRB 081028, Swift-BAT refined analysis
  32. GRB 081028: Enhanced Swift-XRT position
  33. GRB 081028: TAROT Calern observatory optical observations
  34. GRB 081028: optical observations at the NOT
  35. GRB 081028: GROND Detection of the Optical/NIR Afterglow Candidate
  36. Fermi LAT/GBM short-hard GRB 081024B: Possible TLS Afterglow (Corrected)
  37. Fermi LAT/GBM short-hard GRB 081024B: Possible TLS Afterglow
  38. GRB 081028: Swift detection of a burst
  39. GRB 081024: No radio detection with the VLA
  40. GRB081025: RTT150 optical observations
  41. GRB081024B: P200 Observations
  42. GRB 081024B: Swift-XRT further observations
  43. GRB 081025 BAT refined analysis
  44. Swift UVOT observations of GRB081024B
  45. Konus-Wind observation of GRB 081025
  46. GRB 081025: Swift-XRT position
  47. GRB 081024B: Swift-XRT observations
  48. GRB 081025: Burst detection from Swift-BAT slew data
  49. GRB 081024: Swift-XRT refined analysis
  50. GRB 081024, Swift-BAT refined analysis
  51. GRB 081024: Enhanced Swift-XRT position
  52. GRB 081024: Faulkes Telescope North optical observations
  53. GRB 081024A: ROTSE-III Optical Limits
  54. GRB 081024: Swift detection of a burst
  55. GRB 081022, Swift-BAT refined analysis
  56. GRB 081016A: Swift-XRT refined analysis
  57. Swift detection of a possible burst (trigger 332287)
  58. GRB 081017, Swift-BAT refined analysis
  59. GRB 081017: REM early observations
  60. GRB 081016B, Swift-BAT refined analysis
  61. GRB 081011: Swift XRT refined analysis
  62. GRB 081016B: Swift-XRT Team refined Analysis
  63. GRB 081016B: Enhanced Swift-XRT position
  64. GRB 081016B: ROTSE-III Optical Limits
  65. GRB 081016B: Swift detection of a burst
  66. GRB 081011: Enhanced Swift-XRT position
  67. Swift detection of flare on CC Eri
  68. GRB 081016: A long GRB discovered by INTEGRAL
  69. Trigger 331721 Due to Swift startracker loss-of-lock
  70. Detection of flare star Algol in Swift-BAT slew data
  71. GRB 081009: Fermi GBM detection
  72. GRB 081012: GROND upper limits
  73. Swift-BAT triggered on the flare star Algol
  74. GRB 081012: Fermi GBM detection
  75. GRB 081007 and GRB 081007B: Fermi GBM detection
  76. GRB 080430: optical observations
  77. GRB 081012: Observations from NOT
  78. GRB 081012: Swift/XRT detection
  79. GRB 081012, Swift-BAT refined analysis
  80. GRB081011: UVOT detection of an optical afterglow
  81. GRB 081011: Swift/XRT detection
  82. GRB 081011, Swift-BAT refined analysis
  83. GRB 081008, SMARTS optical/IR afterglow observations
  84. GRB 081011: Swift detection of a burst
  85. GRB 081007: Radio Detection
  86. GRB 081008, Swift-BAT refined analysis
  87. GRB 081008: Swift-XRT Refined Analysis
  88. GRB081008: Swift/UVOT observations
  89. GRB 081008: Enhanced Swift-XRT position
  90. GRB 081008: Swift detection of a burst with optical afterglow
  91. GRB 081008: ROTSE-III Detection of Optical Counterpart
  92. GRB081006B: Fermi GBM detection
  93. GRB081006: Fermi GBM detection
  94. GRB081007: Swift/UVOT Observations
  95. GRB 081007, SMARTS optical afterglow observations
  96. GRB 081007, Swift-BAT refined analysis
  97. GRB 081007: Early RAPTOR measurements of optical counterpart
  98. GRB 081007: Swift-XRT Team refined analysis
  99. GRB 081007: Enhanced Swift-XRT position
  100. GRB 081007, Faulkes Telescope North optical observations

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