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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"

25779 results found.

  1. GRB 081126: Swift detection of a burst
  2. GRB 081125: Fermi GBM detection
  3. GRB 081124: Fermi GBM detection
  4. GRB 081120: Fermi GBM detection
  5. GRB 081118: Fermi GBM detection.
  6. GRB 081122: Fermi GBM detection
  7. GRB 081121, SMARTS optical/IR afterglow observations
  8. GRB081121: Refined Swift/UVOT observations
  9. GRB 081121: Swift-XRT refined analysis
  10. GRB 081121: Enhanced Swift-XRT position
  11. GRB 081121: GROND observations
  12. GRB 081121: Swift-BAT refined analysis
  13. GRB081121: Swift/UVOT observations
  14. GRB081118 : optical upper limit
  15. GRB 081119: Fermi GBM detection
  16. VLA Radio upper limit on GRB 081118
  17. GRB 081118: Swift-XRT refined analysis
  18. GRB 081118: GROND detection of afterglow
  19. GRB 081118: optical afterglow candidate
  20. GRB 081118: Swift UVOT Upper Limits
  21. GRB 081118: Enhanced Swift-XRT position
  22. GRB 081118: Swift detection of a burst
  23. GRB 081109A: confirmation of possible detection host galaxy
  24. Further Swift-XRT observations of the probable GRB 081105.
  25. GRB 081113: Fermi GBM detection
  26. GRB 081102: RTT150 Optical observations
  27. GRB 081110: Fermi GBM detection
  28. GRB 081109: TAROT La Silla observatory optical observations
  29. GRB 081102: MASTER refind and final results
  30. GRB 081109: GROND redshift limit and host extinction
  31. GRB 081025: Swift-XRT further analysis
  32. GRB 081024B: Swift-XRT late-time observations
  33. GRB 081109: GROND Detection of the Optical/NIR Afterglow Candidate
  34. GRB 081109A: Swift-XRT refined analysis
  35. GRB 081109: Fermi GBM detection
  36. Swift-BAT Trigger 334129: possible burst
  37. GRB 081109: REM NIR afterglow detection
  38. GRB 081109: Swift detection of a burst
  39. GRB 081024C: Fermi Gamma-ray Burst Monitor detection
  40. SGR 1806-20: Fermi GBM detection
  41. GRB 081102B: Fermi GBM detection
  42. GRB 081105B: Fermi GBM detection
  43. GRB 081107: Fermi GBM detection
  44. GRB 081104: GROND found no Optical/NIR Afterglow
  45. GRB 081105: GROND Upper Limits
  46. Radio observation of GRB 080523 with ATCA
  47. Radio observation of GRB 080520 with ATCA
  48. GRB 081105: Observations from OSN
  49. Swift-XRT observations of GRB 081105
  50. GRB 081101B: Fermi GBM detection
  51. Radio observation of GRB 080516 with ATCA
  52. GRB 081105 Swift/BAT and IPN Localization
  53. GRB 081025: Fermi GBM observation
  54. GRB 081104: GROND Detection of the Optical/NIR Afterglow Candidate?
  55. GRB 081104: refined XRT analysis
  56. GRB 081104: Enhanced Swift-XRT position
  57. Fermi-GBM detection of a Solar Flare
  58. Fermi Detection of GRB 081102
  59. GRB 081104 : Faulkes Telescope South observations
  60. Radio observation of GRB 080130 with ATCA
  61. GRB 081102: MASTER prompt optical limit
  62. GRB 081102: Swift-XRT refined analysis
  63. GRB 081102: Enhanced Swift-XRT position
  64. Radio observation of GRB 080218b with ATCA
  65. Radio observation of GRB 080229a with ATCA
  66. GRB 081102: MASTER VWF promt observation
  67. GRB 081102: Swift detection of a burst
  68. SGR 0501+4516: optical observations in August
  69. GRB 081101 (or SGR 0623-0006 ): Fermi GBM detection
  70. SGR 0623-0006 or GRB 081101: Swift-XRT refined analysis
  71. SGR 0623-0006 or GRB 081101: Swift-BAT/-XRT refined analysis
  72. GRB 081024B: BTA deep optical observations
  73. GRB 081024B: new Swift-XRT observations
  74. Radio observation of GRB 080229b with ATCA
  75. GRB 081024B: VLA radio observation
  76. GRB 081029: UVOT Detection of the Optical Afterglow
  77. GRB081029: Swift XRT refined analysis
  78. GRB 081025: Suzaku WAM observation of the prompt emission
  79. GRB 081024B: Suzaku WAM observation of the prompt emission
  80. GRB 081029: Enhanced Swift-XRT position
  81. GRB 081028: GROND Confirmation of the Optical/NIR Afterglow
  82. GRB 081029: REM observations
  83. Radio observation of GRB 080303 with ATCA
  84. Radio observation of GRB 080411 with ATCA
  85. GRB 081029: GROND Detection of the Optical/NIR Afterglow
  86. GRB 081028B: Fermi GBM detection
  87. GRB 081021: Fermi GBM detection
  88. Swift UVOT observations of GRB081028
  89. GRB 081028: Swift-XRT refined analysis
  90. GRB 081028: Enhanced Swift-XRT position
  91. GRB 081028: TAROT Calern observatory optical observations
  92. GRB 081028: optical observations at the NOT
  93. GRB 081028: GROND Detection of the Optical/NIR Afterglow Candidate
  94. Fermi LAT/GBM short-hard GRB 081024B: Possible TLS Afterglow (Corrected)
  95. Fermi LAT/GBM short-hard GRB 081024B: Possible TLS Afterglow
  96. GRB 081028: Swift detection of a burst
  97. GRB 081025: TLS upper limits
  98. GRB 081024: No radio detection with the VLA
  99. GRB081025: RTT150 optical observations
  100. GRB081024B: P200 Observations

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