International audienceCEA LIST is working on the development of a high-sensitivity thermal neutron counter, based on the insertion of gadolinium in spherical plastic scintillators. As the radiation sensor comprises one or several volumes of scintillating polymers, it is, by nature, sensitive to both neutron and gamma radiations. This property allows the development of a versatile detector, provided that it is possible to algorithmically separate the signature of both types of radiations. The technologically building brick is, moreover, to be implemented in a transportable (<15 kg) system, handled by a first intervention task force in an exposed area. The aim of this paper is to study, both through Monte Carlo simulation and experimentally, ...