The AD775 cosmic event revisited: the Sun is to blame

  title={The AD775 cosmic event revisited: the Sun is to blame},
  author={Ilya G. Usoskin and Bernd Kromer and Fitz Hugh Ludlow and J{\"u}rg Beer and M. Friedrich and Gennady A. Kovaltsov and Sami K. Solanki and Lukas Wacker},
  journal={Astronomy and Astrophysics},
Aims. Miyake et al. (2012, Nature, 486, 240, henceforth M12) recently reported, based on 14 C data, an extreme cosmic event in about AD775. Using a simple model, M12 claimed that the event was too strong to be caused by a solar flare within the standard theory. This implied a new paradigm of either an impossibly strong solar flare or a very strong cosmic ray event of unknown origin that occurred around AD775. However, as we show, the strength of the event was significantly overestimated by M12… Expand

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