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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 080319B: Jet Break, Energetics, Supernova
  2. GRB 080413B: Faulkes Telescope South optical afterglow observations
  3. GRB 080413A: Liverpool Telescope and Faulkes Telescope South optical observations
  4. GRB 080413A: Suzaku WAM observation of the prompt emission
  5. GRB 080413B: Suzaku WAM observation of the prompt emission
  6. GRB 080413A: MOA-II optical afterglow observations
  7. GRB 080319B: Continued Gemini-N monitoring
  8. GRB 080414: RTT150 optical observations
  9. GRB 080414 Watcher observations
  10. GRB 080414: A long GRB detected by INTEGRAL
  11. VLA radio observations of GRB 080413B
  12. GRB 080413A: Gemini-South Spectroscopy
  13. GRB 080413B: Gemini-South Spectroscopy
  14. VLA radio observations of GRB 080413A
  15. IBAS Alert n. 5257 : not a GRB
  16. GRB 080413B: Ep,i-Eiso correlation
  17. GRB080413B
  18. Swift-BAT spectral lag analysis of GRB 080413B
  19. GRB 080413a, SMARTS optical/IR afterglow observations
  20. GRB 080413B: Swift XRT refined analysis
  21. GRB080413A: Swift/UVOT observations
  22. GRB 080413B, Swift-BAT refined analysis
  23. GRB 080413A: Swift-XRT refined analysis
  24. GRB 080413A, Swift-BAT refined analysis
  25. GRB 080413A Bootes observation
  26. GRB 080413A: VLT/UVES redshift
  27. GRB 080413B: VLT redshift
  28. GRB080413B: REM NIR & Optical Observation
  29. GRB 080413B: GROND detection of afterglow in all bands
  30. GRB 080413B: Swift detection of a possibly short burst with optical counterpart
  31. GRB 080413A: REM detection of the NIR Afterglow
  32. GRB 080413: Enhanced Swift-XRT position
  33. GRB 080413: TAROT Calern observatory optical observations
  34. GRB 080413: Swift detection of a burst with an optical afterglow
  35. GRB 080413: ROTSE-III Detection of Optical Counterpart
  36. GRB 080411: Swift/UVOT refined analysis
  37. GRB 080411, Swift-BAT refined analysis
  38. GRB 080411: Swift-XRT Refined Analysis
  39. Konus-Wind observation of GRB 080411
  40. GRB 080411: Enhanced Swift-XRT position
  41. GRB 080411: VLT redshift
  42. GRB 080411: GROND detection of optical afterglow candidate
  43. GRB080330: MAGIC telescope GeV observation
  44. GRB 080411: Swift detection of a bright burst
  45. GRB 080330: Swift-XRT refined position retraction
  46. GRB 080409: Swift-BAT refined analysis
  47. GRB 080408: GROND detection of optical/NIR afterglow candidate
  48. GRB 080330 optical observations
  49. Swift/UVOT observations of GRB080409
  50. GRB 080409: Swift XRT refined analysis
  51. UVOT/Swift Observations of GRB080408
  52. GRB 080408: Swift-XRT position of a possible afterglow
  53. GRB 080409: Enhanced Swift-XRT position
  54. GRB 080409: REM optical/NIR observations
  55. GRB 080409: Swift detection of a burst
  56. GRB 080408: Analysis of AGILE Gamma-ray data
  57. GRB 080408: GRB Localization by SuperAGILE
  58. GRB 080319A: Early RAPTOR optical limits
  59. GRB 080319B: HST observations
  60. GRB 080330: RAPTOR detection of prompt optical flash
  61. GRB 080319B: Potential Jet Break Observed by Swift-XRT and UVOT
  62. GRB 080405: Swift-BAT refined analysis
  63. GRB 080405: Swift-XRT position
  64. GRB 080405: Mars Oddysey and Swift-BAT detection, possible host galaxy
  65. GRB 080325: optical upper limit
  66. GRB 080328: GAO 150cm telescope Optical Observation
  67. GRB080330: Improved Swift XRT Position
  68. GRB 080330: Prompt PROMPT Observations
  69. GRB080330: optical observations
  70. GRB 080319B: TORTORA light curve (Correction)
  71. GRB080328, RIMOTS optical upper limit
  72. GRB080330: optical observations
  73. GRB080330: Swift XRT refined analysis
  74. GRB 080330: REM optical observations
  75. GRB 080330, SMARTS optical/IR afterglow observations
  76. GRB 080330 Swift-UVOT refined analysis
  77. GRB 080328: Suzaku WAM observation of the prompt emission
  78. GRB080330: TNT optical observations
  79. GRB 080330, Swift-BAT refined analysis
  80. Konus-Wind observation of GRB 080328
  81. GRB 080330: Redshift Confirmation from Hobby-Eberly Telescope Spectroscopy
  82. GRB080330: LOAO R-band Detection
  83. GRB 080330: GROND Observations
  84. GRB 080330: NOT redshift
  85. GRB 080330: TAROT Calern observatory optical observations
  86. GRB 080330A: PAIRITEL Infrared Detections
  87. GRB 080330: error in reported XRT position
  88. GRB080330 - SDSS Pre-Burst Observations
  89. GRB 080330: Liverpool Telescope Optical observations
  90. GRB 080330A: ROTSE-III Detection of Optical Counterpart
  91. GRB 080330: Swift detection of a burst with an optical counterpart
  92. GRB 080330: TAROT Calern observatory optical detection
  93. GRB 080319B: Continued Gemini-South followup and possible host galaxy
  94. GRB 080328: BTA optical imaging and spectroscopy
  95. GRB 080328, Swift-BAT refined analysis
  96. GRB 080328: Swift XRT refined analysis
  97. GRB 080325, Swift-BAT refined analysis
  98. Swift/UVOT observations of GRB080328
  99. GRB080325 - I and z-band Imaging
  100. GRB080319B, BVRcIc field calibration

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