Fast neutron flux analyzer with real-time digital pulse shape discrimination

Abstract Investigation of subthermonuclear plasma confinement and heating in magnetic fusion devices such as GOL–3 and GDT at the Budker Institute (Novosibirsk, Russia) requires sophisticated equipment for neutron-, gamma- diagnostics and upgrading data acquisition systems with online data processing. Measurement of fast neutron flux with stilbene scintillation detectors raised the problem of discrimination of the neutrons ( n ) from background cosmic particles (muons) and neutron-induced gamma rays ( γ ). This paper describes a fast neutron flux analyzer with real-time digital pulse-shape discrimination (DPSD) algorithm FPGA-implemented for the GOL–3 and GDT devices. This analyzer was tested and calibrated with the help of 137 Cs and 252 Cf radiation sources. The Figures of Merit (FOM) calculated for different energy cuts are presented.