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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"

25783 results found.

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

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