Nuclear Engineering ETDs


Rodney Keith

Publication Date



Intermodal shipping containers entering the United States provide an avenue to smuggle unsecured or stolen special nuclear material (SNM). The only direct method fielded to indicate the presence of SNM is by passive photon/neutron radiation detection. Active interrogation using neutral particle beams to induce fission in SNM is a method under consideration. One by-product of fission is the creation of fragments that undergo radioactive decay over a time period on the order of tens of seconds after the initial event. The delayed' gamma-rays emitted from these fragments over this period are considered a hallmark for the presence of SNM. A fundamental model is developed using homogenized cargos with a SNM target embedded at the center and computationally interrogated using simultaneous neutron and photon beams. Findings from analysis of the delayed gamma emissions from these experiments are intended to mitigate the effects of poor quality information about the composition and disposition of suspect cargo before examination in an active interrogation portal.


active interrogation, neutral particle beam, intermodal container, special nuclear material


This work was partially supported by contract DTRA01-03-D-0009-0025 from the Defense Threat Reduction Agency, Department of Defense.

Document Type




Degree Name

Nuclear Engineering

Level of Degree


Department Name

Nuclear Engineering

First Committee Member (Chair)

Hecht, Adam

Second Committee Member

Arthur, Edward

Third Committee Member

Middleton, Bobby

Fourth Committee Member

Ross, Timothy