| 摘要 |
FIELD: physics.SUBSTANCE: method includes irradiating an analysed object with neutron flux, measuring the energy spectrum of the induced gamma-radiation, simultaneously detecting at least two gamma-radiation quanta of one nuclear cascade using at least two gamma-radiation detectors, signals from which are picked up under the condition of coinciding time, and performing automated analysis of the obtained spectrum with a computer, wherein the scanned object is irradiated with a directed beam of neutrons with energy 14.1 MeV, emitted by a generator based on a T(d,n)4He reaction with a built-in alpha-particle detector; recording the time and direction of neutron emission; detecting gamma-radiation quanta from inelastic nuclear reactions while fast neutrons pass through the analysed object; analysing pairs of gamma-radiation quanta which coincide in time with the signal from the alpha-particle detector taking into account the neutron flight time; based on the measured energies of the pairs of gamma-radiation quanta, constructing a two-dimensional correlation spectrum and based on values in the region of characteristic peaks of chemical elements of interest, determining their concentration in the scanned object.EFFECT: rapid determination of concentration of target elements in an analysed object, improved spatial resolution, low minimum detectable mass of the substance of interest, low level of false alarm and shorter time for processing the recorded spectrum.4 dwg |
