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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. GRB 101224A: Fermi GBM observation
  2. GRB 101224A: Swift-XRT refined Analysis
  3. GRB101224A: MITSuME Okayama optical upper limits
  4. GRB 101224A, Swift-BAT refined analysis
  5. GRB 101224A - UVOT-enhanced XRT position
  6. GRB 101224A: Swift detection of a short burst
  7. GRB 101219A: Chandra Observations
  8. GRB 101219B: Swift/UVOT refined analysis
  9. GRB 101219B: Swift-XRT refined Analysis
  10. GRB 101219B: Enhanced Swift-XRT position
  11. GRB 101219A: MITSuME Ishigakijima Optical upper limits
  12. GRB 101219B: GROND Detection of the Optical/NIR Afterglow
  13. GRB 101219B: Fermi GBM observation
  14. GRB 101219A: IAC80 optical observations
  15. GRB 101219B: Swift-BAT refined analysis
  16. GRB 101219A: Swift-XRT refined Analysis
  17. GRB 101219B: Swift detection of a burst with an optical afterglow
  18. GRB 101219A: Swift/UVOT Upper Limits
  19. GRB 101219A: GROND Upper limits
  20. Konus-Wind observation of short hard GRB 101219A
  21. GRB 101219A: Magellan NIR observations
  22. GRB 101219A: Further Gemini-South Imaging
  23. GRB 101219A: Swift-BAT refined analysis
  24. GRB 101219A - NOT observation - upper limit
  25. GRB 101219A: SARA-N Upper Limit
  26. GRB 101219A: Gemini-South observations
  27. GRB 101219A: REM optical and NIR observations
  28. GRB 101219A: ROTSE-III Optical Limits
  29. GRB 101219A: Swift detection of a short hard burst
  30. Request for Supernova related data for GRB 101023A
  31. GRB 101213A : Suzaku WAM observation of the prompt emission
  32. Redshift solution(s) for GRB101213A from Swift-XRT data
  33. Konus-Wind observation of GRB 101213A
  34. XRF 101117A, RIMOTS optical upper limits
  35. GRB 101213A: Fermi GBM observation
  36. GRB 101213A, Swift-BAT refined analysis
  37. GRB 101213A: Swift-XRT refined Analysis
  38. GRB 101213A: Swift/UVOT Upper Limits
  39. GRB 101213A: Enhanced Swift-XRT position
  40. GRB 101213: object within the X-ray error circle
  41. GRB 101213A: Swift detection of a burst
  42. GRB101204A: Swift/UVOT observations
  43. GRB 101204A: Swift-XRT refined Analysis
  44. GRB101204A GROND Detection of the Optical/NIR Afterglow
  45. GRB 101204A Afterglow Candidate, VATT Observations
  46. GRB 101129A : Suzaku WAM observation of the prompt emission
  47. GRB 101204A Swift-XRT/UVOT afterglow candidate
  48. Konus-Wind observation of GRB 101130A
  49. GRB 101204A detected in ground analysis of BAT data
  50. Konus-Wind observation of GRB 101129A
  51. IPN Localization of GRB101130 (possible short duration burst)
  52. GRB 101129A SHB found by IPN and in ground analysis of BAT data
  53. GRB101030A
  54. GRB 101201A: Fermi GBM observation
  55. GRB 101201A: Swift-XRT refined Analysis
  56. GRB 101201A: Swift/UVOT Detection
  57. GRB 101201A: GROND Detection of the Optical/NIR Afterglow
  58. GRB 101201A detected in ground analysis of BAT data
  59. Swift detection of MAXIJ1409-619
  60. GRB 101123A: ROTSE optical observations
  61. GRB 101123A: MASTER prompt optical observations
  62. Konus-Wind observation of GRB 101123A
  63. IPN triangulation of bright GRB 101123A
  64. GRB 101123A: Fermi GBM detection
  65. Optical observation of GRB 101024A
  66. GRB 101117B: GROND Upper limits
  67. GRB 101117B: Swift/UVOT Observations of the Optical Afterglow
  68. GRB 101112A: OSN and BTA observations
  69. XRF 101117A: Palomar Transient Factory Observations
  70. GRB 101117B: Swift-XRT refined analysis
  71. GRB101114A: Swift/UVOT Upper Limits
  72. GRB 101114A: Confirmation of the X-ray afterglow
  73. GRB 101117B: Swift-BAT refined analysis
  74. GRB 101117B: Enhanced Swift-XRT position
  75. GRB 101117B: Swift/UVOT Discovery of an Optical Afterglow
  76. GRB 101117B: Swift detection of a burst
  77. XRF101117A: MAXI/GSC detection of a short X-ray transient
  78. GRB 101114A: GROND Upper limits
  79. Konus-Wind observation of GRB 101114A
  80. Fermi GBM detection of a burst from a galactic source
  81. GRB 101114A: Swift-XRT candidate afterglow detection and analysis
  82. GRB 101114A, Swift-BAT GRB detected by ground processing
  83. Possible detection of INTEGRAL burst GRB 101112A by the EVLA
  84. GRB 101112A: Fermi GBM detection
  85. GRB 101112A: optical observations
  86. GRB 10112A: MASTER optical observations
  87. Konus-Wind observation of GRB 101112A
  88. GRB 101112A - XRT source detection/analysis
  89. GRB 101112A: BOOTES-2/TELMA optical afterglow candidate
  90. GRB101112A: Liverpool Telescope Afterglow Candidate
  91. GRB 101112A: a long GRB detected by INTEGRAL
  92. GRB 100906A: optical observations
  93. GRB 090113, the review of the sky area in plate archives
  94. GRB 101030A : MOA optical observation
  95. GRB 101030A: GROND optical/NIR afterglow candidate
  96. GRB 101030A : Swift XRT refined analysis
  97. GRB 101030A: Swift/UVOT Upper Limits
  98. GRB 101030A: Swift-BAT refined analysis
  99. GRB 101030A: Enhanced Swift-XRT position
  100. GRB 101030A: Swift detection of a burst

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