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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"

21393 results found.

  1. VLA non-detection of GRB 071010A
  2. GRB 071011, Optical afterglow
  3. GRB 071011: Confirmation of P60 optical afterglow
  4. GRB 071011: Kanazawa Optical limits
  5. GRB 071011: P60 Optical Afterglow Candidate
  6. GRB 071011: MARGE Optical Limits
  7. GRB 071011: XRT afterglow detection
  8. GRB 071011, Swift-BAT refined analysis
  9. GRB 071011: Early Super-LOTIS Observations
  10. GRB 071010B: Bright OT confirmed with TLS
  11. GRB 071011: Swift detection of a burst
  12. Optical Observation: GRB 071010
  13. Optical observations: GRB 071010A
  14. Konus-Wind observation of GRB 071010B
  15. GRB071010B: Swift/XRT detection
  16. GRB 071010B, Swift-BAT refined analysis
  17. GRB 071006, Swift-BAT refined analysis
  18. GRB071008: optical observations
  19. GRB 071010B: Swift detection of a burst
  20. GRB 071010: Swift-XRT observation
  21. GRB 071008, Swift-BAT refined analysis
  22. GRB 071010, Swift-BAT refined analysis
  23. GRB071008: Swift-XRT observation
  24. GRB 071010: TAROT La Silla observatory detection of the afterglow
  25. GRB 071010: Swift detection of a burst
  26. GRB 071006 Swift-BAT detection of a burst
  27. GRB071008: IAC80 observation
  28. GRB 071008: Swift detection of a burst
  29. GRB 071003: XRT refined analysis
  30. GRB070920A: MAGIC telescope GeV observation
  31. Radio detection of GRB 071003 with the VLA
  32. GRB 070810B: further XRT analysis
  33. Konus-Wind observation of GRB 071003
  34. GRB 071003: Swift XRT position
  35. GRB 071003, Swift-BAT refined analysis
  36. GRB 071003: MARGE Observations
  37. GRB 071003 Optical observations
  38. GRB 071003: KAIT optical afterglow observations
  39. GRB 071003: Swift detection of a bright burst
  40. GRB 070714B: host galaxy spectroscopic redshift
  41. GRB 071001: Swift-XRT Team refined analysis
  42. GRB 071001, Swift-BAT refined analysis
  43. Faulkes Telescope South observations of GRB 071001
  44. GRB 071001: Swift detection of a burst
  45. VLA observation of GRB 070923
  46. Disregard the Swift-XRT Notices today
  47. GRB070925: Swift-XRT Afterglow confirmation
  48. GRB 070925: Gemini South Imaging
  49. GRB070925: Swift-XRT Position
  50. Update on Swift Status
  51. GRB 070920B: ROTSE-III Early Optical Limits
  52. Recent SGR1806-20 Activity
  53. GRB 070923, Swift-BAT refined analysis
  54. GRB 070920B: XRT observations
  55. GRB 070923: Swift detection of a short hard burst
  56. GRB 070917: Suzaku/WAM observation of the prompt emission
  57. GRB 070920B: TAROT La Silla observatory optical observations
  58. GRB 070917: Confirmation of the X-ray afterglow
  59. GRB 070920B, Swift-BAT refined analysis
  60. GRB 070911: Swift/BAT and Suzaku/WAM joint spectral analysis
  61. GRB 070920B: NOT optical observations
  62. GRB 070920B: Swift detection of a burst
  63. GRB 070920, Swift-BAT refined analysis
  64. GRB 070920: TAROT Calern observatory optical observations
  65. GRB 070920: Swift detection of a burst
  66. SGR1806-20: Swift-BAT detection of enhanced activity
  67. GRB070917: optical observations
  68. GRB 070917: P60 Observations
  69. GRB 070917: pseudo-z= 2.40 from prompt emission spectrum
  70. Konus-Wind observation of GRB 070917
  71. Swift Status and XRT Calibration Uncertainties
  72. GRB 070917: Swift-XRT observations
  73. GRB 070917: KAIT optical limits
  74. GRB 070917: R band observations
  75. GRB 070917, Swift-BAT refined analysis
  76. GRB 070917: Swift detection of a bright burst
  77. GRB 070911: Suzaku WAM observation of the prompt emission
  78. GRB 070913: Swift-XRT detection of the possible X-ray afterglow
  79. GRB 070809: The Swift evidence for the SHB nature of this burst
  80. GRB 070913: Swift-BAT refined analysis
  81. GRB 070913: Corrected BAT position
  82. GRB 070913: TAROT La Silla observatory optical observations
  83. GRB 070913: Swift detection of a burst
  84. Swift-BAT Notices back to autonomous real-time distribution
  85. GRB 070911: PAIRITEL IR Observations
  86. GRB 070911: Swift XRT refined analysis
  87. GRB 070911, Swift-BAT refined analysis
  88. GRB 070911: Swift detection of a burst
  89. IPN search for a GRB associated with TAROT transient on August 31
  90. Intense burst from SGR 1806-20 detected on September 7
  91. GRB 070810b: Image Subtraction of Multiple Keck Observations
  92. GRB 070824 - Combined SuperAGILE/IPN Localization
  93. GRB 070731: Swift/UVOT Upper Limit
  94. GRB 070805: UVOT afterglow candidate retraction
  95. GRB070810b: optical candidate
  96. GRB 070810A: ROTSE-III Refined Analysis
  97. Swift observatory off line
  98. GRB 070810B : Faulkes Telescope South Observations
  99. GRB 070810B: Keck spectroscopy of possible host galaxies
  100. GRB070810B: Swift/UVOT Upper Limits

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