• T.-S. F. Wang, J. T. Kwan
  LANL, Los Alamos, New Mexico

The technical feasibility of an explosives detection system based on the nuclear resonance absorption (NRA) of gamma rays in nitrogen-rich materials was demonstrated at Los Alamos National Laboratory (LANL) in 1993 by using an RFQ proton accelerator and a tomographic imaging prototype.* The study is being continued recently to examine deployment of such an active interrogation system in realistic scenarios. The approach is to use a cyclotron and electron-cooling-equipped storage rings(s) to provide the high quality and high current proton beam needed in a practical application. In this work, we investigate the storage ring requirements for a variant of the airport luggage inspection system considered in the earlier LANL experiments. Estimations are carried out based on the required inspection throughput, the gamma ray yield, the proton beam emittance growth due to scattering with the photon-production target, beam current limit in the storage ring, and the electron cooling rate. Studies using scaling and reasonable parameter values indicate that it is possible to use no more than a few storage rings in a practical NRA luggage inspection system.

*R. E. Morgado et al., SPIE Conf. Proc. 2092, International Society for Optical Engineering, Bellingham, WA, 1993, p. 503.