Apparatus for the characterization of fissile material having at least one neutron radiation detector located in a gamma radiation detection scintillator

Apparatus for characterizing fissile material comprising an enclosure for receiving a quantity of fissile material contained in a receptacle, a neutron emitting source (29) for bombarding said fissile material, means (28, 30) for introducing said source (29) into the enclosure and for removing it from said enclosure, neutron radiation detection means (9), moderator means (2, 4, 6) for thermalizing a fission radiation emitted by said fissile material, means (2, 4, 6) being interposed between the neutron radiation detection means (9) and the fissile material, characterized in that it also has gamma radiation detection means (6, 14), which incorporate a scintillator (6) and at least one photomultiplier (14) associated with said scintillator (6), the scintillator material also constituting the moderator for thermalizing the fast neutrons directly emitted by source (29), as well as the neutrons resulting from spontaneous fissions of the .alpha., n reactions and the neutrons resulting from fissions introduced in the fissle material, the neutron radiation detectors (9) being embedded in the scintillator material (6) constituting the moderator.