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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"

27322 results found.

  1. GRB 081128: Enhanced Swift-XRT position
  2. GRB 081128: Optical observation of xinglong TNT
  3. GRB 081128: Swift detection of a burst
  4. GRB081126: Afterglow photometry from Crni Vrh
  5. GRB 081126: GRT Optical Observation
  6. GRB 081127: Swift/UVOT Upper Limits
  7. GRB 081127: Swift-XRT refined analysis
  8. GRB 081127: Enhanced Swift-XRT position
  9. GRB 081127: Swift-BAT refined analysis
  10. GRB 081126: Swift-XRT refined analysis
  11. GRB 081127: Swift detection of a burst
  12. GRB 081126: Swift/UVOT Observations
  13. GRB 081126: optical observations
  14. GRB 081126: Swift-BAT refined analysis
  15. GRB 081126: Enhanced Swift-XRT position
  16. GRB 081126: TAROT Calern observatory optical observations
  17. GRB 081126: Swift detection of a burst
  18. GRB 081125: Fermi GBM detection
  19. GRB 081124: Fermi GBM detection
  20. GRB 081120: Fermi GBM detection
  21. GRB 081118: Fermi GBM detection.
  22. GRB 081122: Fermi GBM detection
  23. GRB 081121, SMARTS optical/IR afterglow observations
  24. Fermi GBM detection of a weak source
  25. GRB081121: Refined Swift/UVOT observations
  26. GRB 081121: Swift-XRT refined analysis
  27. GRB 081121: Enhanced Swift-XRT position
  28. GRB 081121: GROND observations
  29. GRB 081121: Swift-BAT refined analysis
  30. GRB081121: Swift/UVOT observations
  31. GRB 081121: ROTSE-III Detection of Optical Counterpart
  32. GRB081118 : optical upper limit
  33. GRB 081119: Fermi GBM detection
  34. VLA Radio upper limit on GRB 081118
  35. GRB 081118: Swift-XRT refined analysis
  36. GRB 081118: GROND detection of afterglow
  37. GRB 081118: optical afterglow candidate
  38. GRB 081118: Swift UVOT Upper Limits
  39. GRB 081118: Swift-BAT refined analysis
  40. GRB 081118: Enhanced Swift-XRT position
  41. GRB 081118: Swift detection of a burst
  42. GRB 081109A: confirmation of possible detection host galaxy
  43. Further Swift-XRT observations of the probable GRB 081105.
  44. GRB 081113: Fermi GBM detection
  45. GRB 081102: RTT150 Optical observations
  46. GRB 081110: Fermi GBM detection
  47. GRB 081109: TAROT La Silla observatory optical observations
  48. GRB 081102: MASTER refind and final results
  49. GRB 081109: GROND redshift limit and host extinction
  50. GRB 081025: Swift-XRT further analysis
  51. GRB 081024B: Swift-XRT late-time observations
  52. GRB 081109: GROND Detection of the Optical/NIR Afterglow Candidate
  53. GRB 081109A, Swift-BAT refined analysis
  54. GRB 081109A: Swift-XRT refined analysis
  55. GRB 081109: Fermi GBM detection
  56. Swift-BAT Trigger 334129: possible burst
  57. GRB 081109: REM NIR afterglow detection
  58. GRB 081109: Swift detection of a burst
  59. GRB 081024C: Fermi Gamma-ray Burst Monitor detection
  60. SGR 1806-20: Fermi GBM detection
  61. GRB 081102B: Fermi GBM detection
  62. GRB 081105B: Fermi GBM detection
  63. GRB 081107: Fermi GBM detection
  64. GRB 081104: GROND found no Optical/NIR Afterglow
  65. GRB 081105: GROND Upper Limits
  66. Radio observation of GRB 080523 with ATCA
  67. Radio observation of GRB 080520 with ATCA
  68. GRB 081105: Observations from OSN
  69. Swift-XRT observations of GRB 081105
  70. GRB 081101B: Fermi GBM detection
  71. Radio observation of GRB 080516 with ATCA
  72. GRB 081105 Swift/BAT and IPN Localization
  73. GRB 081025: Fermi GBM observation
  74. GRB 081104: GROND Detection of the Optical/NIR Afterglow Candidate?
  75. GRB 081104: refined XRT analysis
  76. GRB 081104: Enhanced Swift-XRT position
  77. GRB 081104: Swift-BAT refined analysis
  78. GRB 081104 : Faulkes Telescope South observations
  79. Radio observation of GRB 080130 with ATCA
  80. GRB 081102: MASTER prompt optical limit
  81. GRB 081102: Swift-XRT refined analysis
  82. GRB 081102: Swift-BAT refined analysis
  83. GRB 081102: Enhanced Swift-XRT position
  84. Radio observation of GRB 080218b with ATCA
  85. Radio observation of GRB 080229a with ATCA
  86. GRB 081102: MASTER VWF promt observation
  87. GRB 081102: Swift detection of a burst
  88. SGR 0501+4516: optical observations in August
  89. SGR 0623-0006 or GRB 081101: Swift-XRT refined analysis
  90. SGR 0623-0006 or GRB 081101: Swift-BAT/-XRT refined analysis
  91. GRB 081024B: BTA deep optical observations
  92. GRB 081024B: new Swift-XRT observations
  93. Radio observation of GRB 080229b with ATCA
  94. GRB 081024B: VLA radio observation
  95. GRB 081029: UVOT Detection of the Optical Afterglow
  96. GRB 081029: Swift-BAT refined analysis
  97. GRB081029: Swift XRT refined analysis
  98. GRB 081025: Suzaku WAM observation of the prompt emission
  99. GRB 081029: Enhanced Swift-XRT position
  100. GRB 081028: GROND Confirmation of the Optical/NIR Afterglow

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