No abstract

A γ-ray integrated measurement prototype system named HAM-1 has been built up by integrating the technologies of γ-ray detection，spectral analysis and information barrier，which can be used for potential nuclear disarmament verification of plutonium components through the measurement of attributes such as the presence of plutonium，the weapon-grade plutonium and its age. A basic starting point for the development of HAM-1 was to prevent any possible leakage of sensitive weapon design information in the process of measurement. Two embedded ARM controllers were selected as the CPUs of HAM-1 according to the design requirements of information barriers. A code dedicated to HAM-1 has been developed for analyzing the high-resolution γ-ray spectra to accurately determine the attributes. The all-round process of HAM-1 from the spectra sampling to data processing and result display was automatic, during which the sensitive weapon design information was protected from leakage.

It is a key aspect to study security of radioactivity gas in reactor circulation. It is necessary to study the transport process of radioactivity inert gases krypton in plutonium aerosol environment after fission occurrence. The experimental data of Kr87 and Kr88 were analyzed. According to the physical propertics of the two different sources,Kr87/Kr88 ratio variety law was analyzed at different sampling times. The physiced picture and model of transport process in plutonium aerosol environment were established by comparing with experimental data.

It is an important approach to preventing nuclear proliferation that comprehensive nuclear test ban treaty is reached. How to judge whether a nuclear test has happened is a key point. In this paper we investigate a method to distinguish between a nuclear test and leakage from civilian nuclear reactor by measuring inert gas xenon nuclides 133mXe, 133Xe, 135Xe, and 131mXe. The distinction between the nuclear test and the reactor leakage is found by analyzing the variation of nuclide quantity with time in a complex decay chain. Two suspicious events in North Korea are measured and analyzed. In order to verify the theoretical results, an experiment of imitating plutonium irradiated by thermal neutron is designed.