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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"

42619 results found.

  1. GRB 081126: Swift-BAT refined analysis
  2. GRB 081126: Enhanced Swift-XRT position
  3. GRB 081126: TAROT Calern observatory optical observations
  4. GRB 081126: Swift detection of a burst
  5. GRB 081125: Fermi GBM detection
  6. GRB 081124: Fermi GBM detection
  7. GRB 081120: Fermi GBM detection
  8. GRB 081118: Fermi GBM detection.
  9. GRB 081122: Fermi GBM detection
  10. Konus-Wind observation of GRB 081121
  11. GRB 081121, SMARTS optical/IR afterglow observations
  12. GRB081121: Fermi GBM detection
  13. Fermi GBM detection of a weak source
  14. GRB081121: Refined Swift/UVOT observations
  15. GRB 081121: Swift-XRT refined analysis
  16. GRB 081121: Magellan Redshift
  17. GRB 081121: Enhanced Swift-XRT position
  18. GRB 081121: GROND observations
  19. GRB 081121: Swift-BAT refined analysis
  20. GRB081121: Swift/UVOT observations
  21. GRB 081121: Swift detection of a burst
  22. GRB 081121: ROTSE-III Detection of Optical Counterpart
  23. GRB 081016b, SMARTS optical/IR observations
  24. GRB 081119: Fermi GBM detection
  25. VLA Radio upper limit on GRB 081118
  26. GRB 081118: VLT redshift
  27. GRB 081118: Swift-XRT refined analysis
  28. GRB 081118: GROND detection of afterglow
  29. GRB 081118: Swift UVOT Upper Limits
  30. GRB 081118: Swift-BAT refined analysis
  31. GRB 081118: Enhanced Swift-XRT position
  32. GRB 081118: Swift detection of a burst
  33. GRB 081109A: confirmation of possible detection host galaxy
  34. Further Swift-XRT observations of the probable GRB 081105.
  35. GRB 081113: Fermi GBM detection
  36. GRB 081110: Fermi GBM detection
  37. GRB 081110: MASTER: first optical observations Fermi GRB
  38. GRB 081109: TAROT La Silla observatory optical observations
  39. GRB 081102: MASTER refind and final results
  40. GRB 081109: GROND redshift limit and host extinction
  41. GRB 081024B: Swift-XRT late-time observations
  42. Swift-BAT refined analysis of trigger 334129
  43. GRB 081109B: Swift/UVOT refined analysis
  44. GRB 081109: GROND Detection of the Optical/NIR Afterglow Candidate
  45. GRB 081109A: Possible Swift-UVOT detection
  46. GRB 081109A: Faulkes Telescope South observations
  47. GRB 081109A, Swift-BAT refined analysis
  48. GRB 081109A: Swift-XRT refined analysis
  49. GRB 081109: Fermi GBM detection
  50. GRB 081109: Swift/UVOT upper limits
  51. GRB 081109A optical upper limit
  52. Swift-BAT Trigger 334129: possible burst
  53. GRB 081109: REM NIR afterglow detection
  54. GRB 081109: Swift detection of a burst
  55. GRB 081028 - PAIRITEL NIR detection
  56. GRB 081024C: Fermi Gamma-ray Burst Monitor detection
  57. SGR 1806-20: Fermi GBM detection
  58. GRB 081102B: Fermi GBM detection
  59. GRB 081105B: Fermi GBM detection
  60. GRB 081107: Fermi GBM detection
  61. GRB 081104: GROND found no Optical/NIR Afterglow
  62. GRB 081105: GROND Upper Limits
  63. Radio observation of GRB 080523 with ATCA
  64. Radio observation of GRB 080520 with ATCA
  65. GRB 081105: Observations from OSN
  66. UVOT/Swift observations of GRB081105
  67. GRB 081101B: Fermi GBM detection
  68. Radio observation of GRB 080516 with ATCA
  69. GRB 081105 Swift/BAT and IPN Localization
  70. GRB 081025: Fermi GBM observation
  71. GRB 081104: GROND Detection of the Optical/NIR Afterglow Candidate?
  72. GRB 081104: refined XRT analysis
  73. GRB 081104: Enhanced Swift-XRT position
  74. GRB 081104: Swift-BAT refined analysis
  75. GRB081104: Swift/UVOT Upper Limits
  76. Fermi-GBM detection of a Solar Flare
  77. Fermi Detection of GRB 081102
  78. GRB 081104 : Faulkes Telescope South observations
  79. GRB 081104: Swift detection of a burst
  80. Radio observation of GRB 080130 with ATCA
  81. GRB 081102: MASTER prompt optical limit
  82. GRB 081102: Swift-XRT refined analysis
  83. GRB 081102: Swift-BAT refined analysis
  84. GRB 081102: Enhanced Swift-XRT position
  85. Radio observation of GRB 080218b with ATCA
  86. Radio observation of GRB 080229a with ATCA
  87. GRB 081102: MASTER VWF promt observation
  88. GRB 081102: OPTIMA-Burst optical upper limit
  89. GRB 081102: Swift detection of a burst
  90. SGR 0501+4516: optical observations in August
  91. GRB 081101 (or SGR 0623-0006 ): Fermi GBM detection
  92. SGR 0623-0006 or GRB 081101: Swift-XRT refined analysis
  93. SGR 0623-0006 or GRB 081101: Swift-BAT/-XRT refined analysis
  94. Swift-BAT triggered on a probable GRB 081101 (trigger=333320)
  95. GRB 081024B: BTA deep optical observations
  96. GRB 081028: CrAO optical observations
  97. GRB 081024B: new Swift-XRT observations
  98. Radio observation of GRB 080229b with ATCA
  99. GRB 081024B: VLA radio observation
  100. GRB 081029: UVOT Detection of the Optical Afterglow

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