A detection system and method for investigating a content of an item

A detection system and method for investigating a content of an item to be inspected, comprising an inspection area (10) for receiving said item (P) and a neutron generator (N) for generating a directional beam (B) of energetic neutrons, directed towards said inspection area. Detection means are provided that comprise at least one detector (DG, DNl..4) responsive to interaction products coming from said inspection area and impinging thereon substantially along a detection axis (D) upon interaction of said energetic particles with nuclei of material of said item. Said neutron generator (N) is configured to expose said inspection area (10) to a substantially uni-directional beam (B) of energetic neutrons along an interrogation axis (I) through said inspection area. Said directional beam (B) has a cross section that is smaller, particularly at least said several times smaller, than a corresponding cross section of said inspection area (10), more particularly several times smaller than a corresponding cross section of said item (P) to be inspected. Said detection means (DG, DNl..4) detect said interaction products along at least one detection axis (D) upon interaction of said at least substantially unidirectional beam of energetic neutrons with said item to be inspected.