O2 photodesorption from a Ag8O2- cluster K. Koyasu, M. Niemietz, W. Westhäuser and G. Ganteför Eur. Phys. J. D, 53 1 (2009) 59-62 Published online: 18 February 2009 DOI: 10.1140/epjd/e2009-00059-y