Abstract
This paper covers the concept design of an illicit material detection system under the project: "Aviation security-Design of a Nuclear Instrument for Contraband Detection" established by King Abdulaziz University. The detection system is composed of two units. The first unit is an X-ray machine which will indicate a location of interest and the second unit is a neutron based system. The motivation of this project is that the design is based on finding the location of the suspicious object inside the luggage by the first unit. This location will be the point of interest for the neutron based detection system. Since checks by the neutron based system are carried out for only suspicious baggage inspected by X-ray inspection system, occasional delays in the neutron based detection system should be acceptable. In this paper, the engineering description of the system is descried and the neutron based system is simulated using Monte Carlo MCNP code.