The AD775 cosmic event revisited: the Sun is to blame I. G. Usoskin, B. Kromer, F. Ludlow, J. Beer, M. Friedrich, G. A. Kovaltsov, S. K. Solanki and L. Wacker A&A, 552 (2013) L3 Published online: 18 March 2013 DOI: 10.1051/0004-6361/201321080