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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 080426: Swift detection of a possibly short burst
  2. Possible GRB 080315: XRT non-detection of afterglow
  3. GRB 080320 : Faulkes Telescope North Observations
  4. GRB 080319A : Liverpool and Faulkes Telescopes Observations
  5. GRB080319A: MAGIC telescope GeV observation
  6. Swift-BAT trigger 309665 is not a GRB
  7. GRB 080420A: ROTSE-III Optical Limits on a possible short burst
  8. GRB 080420?: Swift detection of a possible short burst
  9. GRB080310, BVRcIc field calibration
  10. GRB 080413A: Suzaku/WAM and Swift/BAT joint spectral analysis
  11. GRB 080413B: Rapid PROMPT Observations
  12. Swift XRT and UVOT observations of GRB080414
  13. GRB 080319B: Jet Break, Energetics, Supernova
  14. GRB 080413B: Faulkes Telescope South optical afterglow observations
  15. GRB 080413A: Liverpool Telescope and Faulkes Telescope South optical observations
  16. GRB 080413A: Suzaku WAM observation of the prompt emission
  17. GRB 080413B: Suzaku WAM observation of the prompt emission
  18. GRB 080413A: MOA-II optical afterglow observations
  19. GRB 080319B: Continued Gemini-N monitoring
  20. GRB 080414: RTT150 optical observations
  21. GRB 080414 Watcher observations
  22. GRB 080414: A long GRB detected by INTEGRAL
  23. VLA radio observations of GRB 080413B
  24. GRB 080413A: Gemini-South Spectroscopy
  25. GRB 080413B: Gemini-South Spectroscopy
  26. VLA radio observations of GRB 080413A
  27. IBAS Alert n. 5257 : not a GRB
  28. GRB 080413B: Ep,i-Eiso correlation
  29. GRB080413B
  30. Swift-BAT spectral lag analysis of GRB 080413B
  31. GRB 080413a, SMARTS optical/IR afterglow observations
  32. GRB 080413B: Swift XRT refined analysis
  33. GRB080413A: Swift/UVOT observations
  34. GRB 080413B, Swift-BAT refined analysis
  35. GRB 080413A: Swift-XRT refined analysis
  36. GRB 080413A, Swift-BAT refined analysis
  37. GRB 080413A Bootes observation
  38. GRB 080413A: VLT/UVES redshift
  39. GRB 080413B: VLT redshift
  40. GRB080413B: REM NIR & Optical Observation
  41. GRB 080413B: GROND detection of afterglow in all bands
  42. GRB 080413B: Swift detection of a possibly short burst with optical counterpart
  43. GRB 080413A: REM detection of the NIR Afterglow
  44. GRB 080413: Enhanced Swift-XRT position
  45. GRB 080413: TAROT Calern observatory optical observations
  46. GRB 080413: Swift detection of a burst with an optical afterglow
  47. GRB 080413: ROTSE-III Detection of Optical Counterpart
  48. GRB 080411: Swift/UVOT refined analysis
  49. GRB 080411, Swift-BAT refined analysis
  50. GRB 080411: Swift-XRT Refined Analysis
  51. Konus-Wind observation of GRB 080411
  52. GRB 080411: Enhanced Swift-XRT position
  53. GRB 080411: VLT redshift
  54. GRB 080411: GROND detection of optical afterglow candidate
  55. GRB080330: MAGIC telescope GeV observation
  56. GRB 080411: Swift detection of a bright burst
  57. GRB 080330: Swift-XRT refined position retraction
  58. GRB 080409: Swift-BAT refined analysis
  59. GRB 080408: GROND detection of optical/NIR afterglow candidate
  60. GRB 080330 optical observations
  61. Swift/UVOT observations of GRB080409
  62. GRB 080409: Swift XRT refined analysis
  63. UVOT/Swift Observations of GRB080408
  64. GRB 080408: Swift-XRT position of a possible afterglow
  65. GRB 080409: Enhanced Swift-XRT position
  66. GRB 080409: REM optical/NIR observations
  67. GRB 080409: Swift detection of a burst
  68. GRB 080408: Analysis of AGILE Gamma-ray data
  69. GRB 080408: GRB Localization by SuperAGILE
  70. GRB 080319A: Early RAPTOR optical limits
  71. GRB 080319B: HST observations
  72. GRB 080330: RAPTOR detection of prompt optical flash
  73. GRB 080319B: Potential Jet Break Observed by Swift-XRT and UVOT
  74. GRB 080405: Swift-BAT refined analysis
  75. GRB 080405: Swift-XRT position
  76. GRB 080405: Mars Oddysey and Swift-BAT detection, possible host galaxy
  77. GRB 080325: optical upper limit
  78. GRB 080328: GAO 150cm telescope Optical Observation
  79. GRB080330: Improved Swift XRT Position
  80. GRB 080330: Prompt PROMPT Observations
  81. GRB080330: optical observations
  82. GRB 080319B: TORTORA light curve (Correction)
  83. GRB080328, RIMOTS optical upper limit
  84. GRB080330: optical observations
  85. GRB080330: Swift XRT refined analysis
  86. GRB 080330: REM optical observations
  87. GRB 080330, SMARTS optical/IR afterglow observations
  88. GRB 080330 Swift-UVOT refined analysis
  89. GRB 080328: Suzaku WAM observation of the prompt emission
  90. GRB080330: TNT optical observations
  91. GRB 080330, Swift-BAT refined analysis
  92. Konus-Wind observation of GRB 080328
  93. GRB 080330: Redshift Confirmation from Hobby-Eberly Telescope Spectroscopy
  94. GRB080330: LOAO R-band Detection
  95. GRB 080330: GROND Observations
  96. GRB 080330: NOT redshift
  97. GRB 080330: TAROT Calern observatory optical observations
  98. GRB 080330A: PAIRITEL Infrared Detections
  99. GRB 080330: error in reported XRT position
  100. GRB080330 - SDSS Pre-Burst Observations

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