HELNED: Helium-3-free low-cost neutron detectors Massimo Barbagallo, Luigi Cosentino, Carmelo Marchetta, Alfio Pappalardo, Carlotta Scirè, Sergio Scirè, Gianfranco Vecchio and Paolo Finocchiaro EPJ Web of Conferences, 79 (2014) 02002 Published online: 10 December 2014 DOI: 10.1051/epjconf/20137902002