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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"

19804 results found.

  1. GRB 081102: Swift detection of a burst
  2. SGR 0501+4516: optical observations in August
  3. SGR 0623-0006 or GRB 081101: Swift-BAT/-XRT refined analysis
  4. GRB 081024B: BTA deep optical observations
  5. GRB 081024B: new Swift-XRT observations
  6. Radio observation of GRB 080229b with ATCA
  7. GRB 081024B: VLA radio observation
  8. GRB 081029: UVOT Detection of the Optical Afterglow
  9. GRB 081029: Enhanced Swift-XRT position
  10. GRB 081028: GROND Confirmation of the Optical/NIR Afterglow
  11. GRB 081029: REM observations
  12. Radio observation of GRB 080303 with ATCA
  13. Radio observation of GRB 080411 with ATCA
  14. GRB 081029: GROND Detection of the Optical/NIR Afterglow
  15. GRB 081028B: Fermi GBM detection
  16. Swift UVOT observations of GRB081028
  17. GRB 081028: Enhanced Swift-XRT position
  18. GRB 081028: TAROT Calern observatory optical observations
  19. GRB 081028: optical observations at the NOT
  20. GRB 081028: GROND Detection of the Optical/NIR Afterglow Candidate
  21. Fermi LAT/GBM short-hard GRB 081024B: Possible TLS Afterglow (Corrected)
  22. Fermi LAT/GBM short-hard GRB 081024B: Possible TLS Afterglow
  23. GRB 081028: Swift detection of a burst
  24. GRB 081024: No radio detection with the VLA
  25. GRB081025: RTT150 optical observations
  26. GRB081024B: P200 Observations
  27. GRB 081024B: Swift-XRT further observations
  28. Swift UVOT observations of GRB081024B
  29. GRB 081025: Swift-XRT position
  30. GRB 081024B: Swift-XRT observations
  31. GRB 081025: Burst detection from Swift-BAT slew data
  32. GRB 081024: Enhanced Swift-XRT position
  33. GRB 081024: Faulkes Telescope North optical observations
  34. GRB 081024A: ROTSE-III Optical Limits
  35. GRB 081024: Swift detection of a burst
  36. GRB 081016A: Swift-XRT refined analysis
  37. Swift detection of a possible burst (trigger 332287)
  38. GRB 081017: REM early observations
  39. GRB 081011: Swift XRT refined analysis
  40. GRB 081016B: Enhanced Swift-XRT position
  41. GRB 081016B: ROTSE-III Optical Limits
  42. GRB 081016B: Swift detection of a burst
  43. GRB 081011: Enhanced Swift-XRT position
  44. Swift detection of flare on CC Eri
  45. Trigger 331721 Due to Swift startracker loss-of-lock
  46. Detection of flare star Algol in Swift-BAT slew data
  47. GRB 081012: GROND upper limits
  48. GRB 081008: Galaxy associated with z=1.967 absorber
  49. Swift-BAT triggered on the flare star Algol
  50. GRB 080430: optical observations
  51. GRB 081012: Observations from NOT
  52. GRB 081012: Swift/XRT detection
  53. GRB 081012, Swift-BAT refined analysis
  54. GRB081011: UVOT detection of an optical afterglow
  55. GRB 081011: Swift/XRT detection
  56. GRB 081008, SMARTS optical/IR afterglow observations
  57. GRB 081011: Swift detection of a burst
  58. GRB 081007: Radio Detection
  59. GRB081008: Swift/UVOT observations
  60. GRB 081008: Enhanced Swift-XRT position
  61. GRB 081008: Swift detection of a burst with optical afterglow
  62. GRB081007: Swift/UVOT Observations
  63. GRB 081007, SMARTS optical afterglow observations
  64. GRB 081007: Early RAPTOR measurements of optical counterpart
  65. GRB 081007: Enhanced Swift-XRT position
  66. GRB 081007, Faulkes Telescope North optical observations
  67. GRB 081007: REM NIR and optical counterpart
  68. GRB 081007: Swift detection of a burst with optical afterglow
  69. GRB081003C: GLAST Burst Monitor detection
  70. GRB 081003B: TAROT Calern observatory optical observations
  71. AXP 1E 1547.0-5408: Swift/UVOT Upper Limits
  72. GRB 081003A: OSN optical observations
  73. GRB 081001: Further observations from OSN
  74. AXP 1E1547.0-5408: Swift-XRT Team refined analysis
  75. GRB 081003A: Swift-XRT Team position and analysis
  76. SGR 1550-5418 = AXP 1E1547.0-5408 (Trigger 330353)
  77. Trigger 330353: Swift detection of a Galactic short soft burst
  78. GRB 081001: Observations from OSN
  79. GRB 081001: Swift UVOT Observations
  80. GRB 081001: Swift-XRT position
  81. GRB 080928: Watcher observations
  82. GRB 080928: GROND DETECTION
  83. GRB 080928: Enhanced Swift-XRT position
  84. GRB 080928: Swift detection of a burst with an optical counterpart
  85. GRB080922, optical upper limit
  86. Swift trigger 325707: Swift/UVOT Upper Limits
  87. Swift trigger 325707: Swift-XRT upper limit
  88. Swift detection of a possible GRB (trigger 325707)
  89. GRB 080922: Swift/UVOT Upper Limits
  90. Trigger 324561: IGR J08408-4503 detected by Swift
  91. GRB 080916C: Fermi GBM Spectral Analysis
  92. GRB 080919: Swift-XRT refined analysis
  93. GRB 080916C: IRSF/SIRUS NIR Observation
  94. GRB 080916C: GROND Confirmation of the Optical Afterglow
  95. GRB 080916C: GROND Confirmation of the Optical Afterglow
  96. GRB 080919: REM NIR observations
  97. GRB 080919: Swift detection of a short burst
  98. GRB 080915A: GROND upper limits
  99. GRB 080916A: GROND lightcurve
  100. GRB 080916C: Swift UVOT Refined Analysis

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