SUMMARY

Increases in globalization and the rise of terror groups since 9/11 have led to an increased risk for proliferation of special nuclear materials (SNM). One of the ways which SNM is likely to be smuggled across borders is through cargo containers at ports of entry. Active interrgoation is a typical method to detect smuggled SNM, but due to stringent throughput requirements, not all cargo containers are scanned. One way to decrease the time and dose required to image a container is to use a monoenergetic gamma-ray beam, rather than a bremsstrahlung x-ray source. Due to the low-energy peaked spectrum of bremsstrahlung x-rays, they are poorly penetrating, leading to an increased scan time and radiation dose to the vicinity. Dual-energy beams, when coupled with spectroscopic detectors can decrease the dose required to produce a high-quality image and provide material identification.

This work focuses on modeling and characterization of an imaging system which employs a low-energy nuclear reaction (LENR) based monoenergetic beam and spectroscopic detectors to improve imaging capabilities in active interrogation. Specifically, we propose methods for dose calculation, Z-effective reconstruction, and tomographic imaging using few views. Furthermore, we characterize the imaging capabilities of a detector array which incorporates quartz Cherenkov-based detectors and LYSO scintillating detectors.