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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"
  1. Konus-Wind observation of GRB 101114A
  2. Fermi GBM detection of a burst from a galactic source
  3. GRB 101114A: Swift-XRT candidate afterglow detection and analysis
  4. GRB 101114A, Swift-BAT GRB detected by ground processing
  5. Possible detection of INTEGRAL burst GRB 101112A by the EVLA
  6. GRB 101112A: Fermi GBM detection
  7. GRB 101112A: optical observations
  8. GRB 10112A: MASTER optical observations
  9. Konus-Wind observation of GRB 101112A
  10. GRB 101112A - XRT source detection/analysis
  11. GRB 101112A: BOOTES-2/TELMA optical afterglow candidate
  12. GRB101112A: Liverpool Telescope Afterglow Candidate
  13. GRB 101112A: a long GRB detected by INTEGRAL
  14. GRB 100906A: optical observations
  15. GRB 090113, the review of the sky area in plate archives
  16. GRB 101030A : MOA optical observation
  17. GRB 101030A: GROND optical/NIR afterglow candidate
  18. GRB 101030A : Swift XRT refined analysis
  19. GRB 101030A: Swift/UVOT Upper Limits
  20. GRB 101030A: Swift-BAT refined analysis
  21. GRB 101030A: Enhanced Swift-XRT position
  22. GRB 101030A: Swift detection of a burst
  23. GRB 090111, the review of the sky area in plate archives (1976-1996)
  24. Konus-Wind observation of GRB 101023A
  25. GRB 101024A: GROND optical/NIR observations
  26. GRB 101024A: Zadko observatory - Gingin. Optical observations refined analysis
  27. GRB 101024A: Swift XRT refined analysis
  28. GRB 101024A: Zadko observatory - Gingin. Optical observations
  29. GRB 101023A: miniTAO/ANIR NIR detection
  30. GRB 101024A: Fermi GBM observation
  31. GRB 101023A: Fermi GBM observation
  32. GRB101024A: Swift/UVOT
  33. GRB 101024A: Swift-BAT refined analysis
  34. GRB 101024A: GRAS06 optical observations
  35. GRB 101024A: Enhanced Swift-XRT position
  36. Swift/UVOT observations of GRB101023A
  37. GRB 101024A: Swift detection of a burst with an optical afterglow
  38. GGRB 101023A: GROND detection of the optical-NIR afterglow
  39. GRB 101023A: Swift-XRT Team Refined Analysis
  40. GRB 101023A: Swift-BAT refined analysis
  41. GRB 101023A: Gemini discovery of optical afterglow
  42. GRB 101023A: Enhanced Swift-XRT position
  43. GRB 101023A: REM NIR observations
  44. GRB 101023A: Swift detection of a burst
  45. GRB 101011A: miniTAO/ANIR NIR upper limits
  46. GRB 101020A: MASTER prompt and afterglow limit
  47. GRB 101020A: BOOTES2 follow-up and limit
  48. GRB 101020A: MASTER polarization optical observations
  49. GRB 101020A, Swift-BAT refined analysis
  50. GRB 101020A: Swift detection of a burst
  51. GRB 101017A: miniTAO/ANIR NIR upper limits
  52. GRB 101017A: Swift XRT refined analysis
  53. GRB 101017A: Swift/UVOT Observations
  54. GRB 101008A: correction to the GCN 11352
  55. GRB 101008A: optical observations
  56. GRB101017A: MITSuME Okayama optical upper limits
  57. Konus-Wind observation of GRB 101017A
  58. GRB 101014A: Fermi LAT detection
  59. GRB 101017A: Enhanced Swift-XRT position
  60. GRB 101017A: Swift-BAT refined analysis
  61. GRB 101017A: ROTSE-III Optical Limits
  62. GRB 101017A: Swift detection of a burst with optical counterpart
  63. GRB 101011A: Fermi GBM detection
  64. GRB 101011A: BOOTES-3 Upper Limit
  65. Konus-Wind observation of GRB 101014A
  66. GRB 101014A: Fermi GBM detection
  67. GRB 100906A: D50 optical detection
  68. GRB 100902A: D50 optical limit
  69. GRB 101011A: Swift/UVOT observations
  70. GRB 101011A, GROND upper limits
  71. GRB 101011A: Zadko observatory - Gingin optical observations
  72. GRB 101011A: XRT Refined Analysis
  73. GRB 101011A: Swift/UVOT Observations of a Possible Optical Afterglow
  74. GRB 101011A: Enhanced Swift-XRT position
  75. GRB 101011A: Swift-BAT refined analysis
  76. GRB 101011A: Swift detection of a burst
  77. GRB 101008A: Fermi GBM observation
  78. GRB 101008A: MASTER prompt optical observations (correction to GCN#11328)
  79. GRB 101008A: MASTER prompt optical observations
  80. GRB 101008A: Swift-BAT refined analysis
  81. GRB101008A, GROND detection of a fading afterglow
  82. GRB 101008A: Swift-XRT refined analysis
  83. GRB 101008A: SAO RAS optical observations
  84. GRB 100915 optical upper limit
  85. GRB 101008: Swift/UVOT Upper Limits
  86. GRB 101008A: Enhanced Swift-XRT position
  87. GRB 101008A: 1.23m CAHA optical observations
  88. GRB 101008A: Swift/XRT Detection of an Afterglow with no UVOT Counterpart
  89. GRB 101008A: Swift detection of a burst
  90. GRB 100728B: X-shooter redshift
  91. Refined analysis shows Swift Trigger 435520 is not a GRB
  92. Swift Trigger 435520 is probably not a GRB
  93. GRB 100925A / MAXI J1659-152: MASTER optical observations
  94. GRB 100924A: Suzaku WAM observation of the prompt emission
  95. GRB 100928A, Swift-BAT refined analysis
  96. GRB 100924A: Fermi GBM observation
  97. GRB 100928A: Swift detection of a burst
  98. GRB 100925A / MAXI J1659-152: WSRT Radio and Polarization Detection
  99. GRB 100925A / MAXI J1659-152: Optical observation with the Kottamia 188cm telescope
  100. GRB100925A/MAXI J1659-152: X-shooter identification as an X-ray binary

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