Analytical model of ionization and energy deposition by proton beams in subcellular compartments Pablo de Vera, Eugene Surdutovich, Isabel Abril, Rafael Garcia-Molina and Andrey V. Solov’yov Eur. Phys. J. D, 68 4 (2014) 96 Published online: 24 April 2014 DOI: 10.1140/epjd/e2014-50041-7