Global concern for the illicit transportation and trafficking of nuclear materials and other radioactive sources is on the rise, with efficient and rapid security and non-proliferation technologies in more demand than ever. Many factors contribute to this issue, including the increasing number of terrorist cells, gaps in security networks, politically unstable states across the globe and the black-market trading of radioactive sources to unknown parties. The use of passive gamma-ray and neutron detection and imaging technologies in security-sensitive areas and ports has had more impact than most other techniques in detecting and deterring illicit transportation and trafficking of illegal radioactive materials. This work reviews and critically evaluates these techniques as currently utilised within national security and non-proliferation applications and proposes likely avenues of development.

Two radiation sensitive scintillators known for their dual sensitivity to neutron and gamma-ray fields are investigated for their pulse discrimination abilities; a lithium glass GS10 inorganic scintillator and a fast organic plastic scintillator EJ-204. Each of these scintillators are optically coupled with an 8 × 8-silicon photomultiplier array to act as a photodetector. Pulse height analysis, the charge comparison method and pulse gradient analysis have all been applied here on neutron and gamma-ray events generated by a Cf-252 source. The three discrimination methods were evaluated based on the figure of merit of the probability density plots generated. Within a GS10 crystal, it has been deduced that pulse height analysis and pulse gradient analysis possess greater abilities to discriminate between the two radiation fields compared to the charge comparison method with both showing a figure of merit of over one. The charge comparison method indicated a lower discrimination ability with a figure of merit around 0.3. When the EJ-204 detector was used, it was deduced that only pulse height analysis exhibits discrimination abilities with a figure of merit around 0.6, while the other two discrimination methods presented no distinction between the two radiation fields.

In this work we evaluated the performance of first-year students of the College of Science and the College of Engineering at Sultan Qaboos University (SQU), Oman on the concepts of electricity and magnetism using the Brief Electricity and Magnetism Assessment (BEMA). The BEMA pre-test and post-test were implemented at the beginning of semester and toward the end of the semester respectively. We investigated the correlation between pre-test and post-test BEMA scores to offer a deeper insight into the students’ understanding of concepts. This study also examined the gain in individual subtopics and compared the BEMA results with the students’ final course grades. The findings indicate that students perform better on questions related to electostatics, struggle more with those related to magnetostatic and have significant difficulties with Faraday’s law. Additionally, a gender-based analysis was conducted, revealing no statistical difference in performance between male and female students.