Multiplasmon excitations in electron spectra of small systems irradiated by swift charged projectiles Phuong Mai Dinh, Paul-Gerhard Reinhard, Eric Suraud and Philipp Wopperer Eur. Phys. J. D, 69 2 (2015) 48 Published online: 17 February 2015 DOI: 10.1140/epjd/e2015-50650-6