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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"

19191 results found.

  1. GRB 071021, Swift-BAT refined analysis
  2. GRB 071021: Swift-XRT Team refined analysis
  3. Konus-Wind observation of GRB 071020
  4. GRB 071021: Swift detection of a burst
  5. GRB 071020: Swift-XRT refined analysis
  6. GRB 071020, Swift-BAT refined analysis
  7. GRB 071020: ROTSE-III Analysis of Optical Counterpart
  8. GRB071020 - SDSS Pre-burst Observations
  9. GRB 071020: Swift detection of a bright burst
  10. GRB 071020A: ROTSE-III Detection of Optical Counterpart
  11. GRB 071018: Mercator Telescope optical observations
  12. Swift autonomous slewing re-enabled
  13. GRB 071018: Swift-XRT observation
  14. GRB 071017 - Swift XRT observations
  15. VLA radio observation of GRB 071018
  16. GRB 071010A: Late-time Keck/LRIS photometry - possible host galaxy and jet break
  17. GRB 071018, Swift-BAT refined analysis
  18. GRB 071018?: Swift detection of a possible burst
  19. GRB 071010B: Suzaku WAM observation of the prompt emission
  20. GRB 071013: 3rd TLS Epoch - constraints on variability
  21. GRB 071013: TLS Upper Limit
  22. VLA detection of radio afterglow of GRB 071010B
  23. VLA non-detection of GRB 071011
  24. GRB 071013: Optical observations
  25. GRB 071013, Swift-BAT refined analysis
  26. GRB 071013: Swift detection of a burst
  27. GRB 071010C Swift-BAT detection of a burst
  28. GRB 071011: Swift-XRT refined analysis
  29. VLA non-detection of GRB 071010A
  30. GRB 071011, Optical afterglow
  31. GRB 071011: MARGE Optical Limits
  32. GRB 071011: XRT afterglow detection
  33. GRB 071011, Swift-BAT refined analysis
  34. GRB 071011: Early Super-LOTIS Observations
  35. GRB 071010B: Bright OT confirmed with TLS
  36. GRB 071011: Swift detection of a burst
  37. Optical Observation: GRB 071010
  38. Optical observations: GRB 071010A
  39. Konus-Wind observation of GRB 071010B
  40. GRB071010B: Swift/XRT detection
  41. GRB 071010B, Swift-BAT refined analysis
  42. GRB 071006, Swift-BAT refined analysis
  43. GRB 071010B: Swift detection of a burst
  44. GRB 071010: Swift-XRT observation
  45. GRB 071008, Swift-BAT refined analysis
  46. GRB 071010, Swift-BAT refined analysis
  47. GRB071008: Swift-XRT observation
  48. GRB 071010: TAROT La Silla observatory detection of the afterglow
  49. GRB 071010: Swift detection of a burst
  50. GRB 071006 Swift-BAT detection of a burst
  51. GRB071008: IAC80 observation
  52. GRB 071008: Swift detection of a burst
  53. GRB 071003: XRT refined analysis
  54. GRB070920A: MAGIC telescope GeV observation
  55. Radio detection of GRB 071003 with the VLA
  56. GRB 070810B: further XRT analysis
  57. Konus-Wind observation of GRB 071003
  58. GRB 071003: Swift XRT position
  59. GRB 071003, Swift-BAT refined analysis
  60. GRB 071003: MARGE Observations
  61. GRB 071003 Optical observations
  62. GRB 071003: KAIT optical afterglow observations
  63. GRB 071003: Swift detection of a bright burst
  64. GRB 070714B: host galaxy spectroscopic redshift
  65. GRB 071001: Swift-XRT Team refined analysis
  66. GRB 071001, Swift-BAT refined analysis
  67. Faulkes Telescope South observations of GRB 071001
  68. GRB 071001: Swift detection of a burst
  69. VLA observation of GRB 070923
  70. Disregard the Swift-XRT Notices today
  71. GRB070925: Swift-XRT Afterglow confirmation
  72. GRB070925: Swift-XRT Position
  73. Update on Swift Status
  74. GRB 070920B: ROTSE-III Early Optical Limits
  75. Recent SGR1806-20 Activity
  76. GRB 070923, Swift-BAT refined analysis
  77. GRB 070920B: XRT observations
  78. GRB 070923: Swift detection of a short hard burst
  79. GRB 070917: Suzaku/WAM observation of the prompt emission
  80. GRB 070920B: TAROT La Silla observatory optical observations
  81. GRB 070917: Confirmation of the X-ray afterglow
  82. GRB 070920B, Swift-BAT refined analysis
  83. GRB 070911: Swift/BAT and Suzaku/WAM joint spectral analysis
  84. GRB 070920B: NOT optical observations
  85. GRB 070920B: Swift detection of a burst
  86. GRB 070920, Swift-BAT refined analysis
  87. GRB 070920: TAROT Calern observatory optical observations
  88. GRB 070920: Swift detection of a burst
  89. SGR1806-20: Swift-BAT detection of enhanced activity
  90. GRB 070917: pseudo-z= 2.40 from prompt emission spectrum
  91. Konus-Wind observation of GRB 070917
  92. Swift Status and XRT Calibration Uncertainties
  93. GRB 070917: Swift-XRT observations
  94. GRB 070917: KAIT optical limits
  95. GRB 070917: R band observations
  96. GRB 070917, Swift-BAT refined analysis
  97. GRB 070917: Swift detection of a bright burst
  98. GRB 070911: Suzaku WAM observation of the prompt emission
  99. GRB 070913: Swift-XRT detection of the possible X-ray afterglow
  100. GRB 070809: The Swift evidence for the SHB nature of this burst

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