Nuclear detectors. Physical principles of operation

Nuclear detection is used in several domains of activity from the physics research, the nuclear industry, the medical and industrial sectors, the security etc. The particles of interest are the α, β, X, γ and neutrons. This article treats of the basic physical properties of radiation detection, the general characteristics of the different classes of existing detectors and the particle/matter interactions: 1 - general considerations; 2 - measurement types and definitions: pulse mode, current mode, definitions; 3 - physical principles of direct detection: introduction and general problem, materials used in detection, simple device, junction semiconductor device, charges generation and transport inside matter, signal generation; 4 - physical principles of indirect detection: introduction, scintillation mechanisms, definition and properties of scintillators. (J.S.)