First acceleration of a proton beam in a side coupled drift tube linac C. Ronsivalle, L. Picardi, A. Ampollini, G. Bazzano, F. Marracino, P. Nenzi, C. Snels, V. Surrenti, M. Vadrucci and F. Ambrosini EPL, 111 1 (2015) 14002 Published online: 30 July 2015 DOI: 10.1209/0295-5075/111/14002