Clogging and unclogging of many-particle systems passing through a bottleneck Iker Zuriguel, Álvaro Janda, Roberto Arévalo, Diego Maza and Ángel Garcimartín EPJ Web Conf., 140 (2017) 01002 Published online: 30 June 2017 DOI: 10.1051/epjconf/201714001002