Interdisciplinary Instrumentation Colloquium

Scintillators for Nuclear Nonproliferation and Nuclear Physics Studies

by Sara Pozzi (Univ. of Michigan)

Auditorium (Building 50)


Building 50

Preventing the spread of nuclear weapons is a top priority for our nation and the world. The Nuclear Nonproliferation Treaty (NPT) entered into force in 1970 to curb the fast-growing expansion of nuclear capabilities of the 1950’s and 60’s; to date, 190 states have signed this treaty, with only a few states remaining non-signatories or having withdrawn. Nevertheless, there are states inside and states outside this treaty that may be pursuing elements of an overt or covert nuclear weapons program. Special nuclear material (SNM) is a major focus because it is the key component in a nuclear explosive device. U-235 in highly-enriched uranium (HEU), plutonium, and U-233 can all be used to sustain an explosive nuclear chain reaction in critical masses that range from kilograms to tens of kilograms. There is a recognized need for both fundamental studies of the emission properties of SNM, including physics of fission studies, and for new detection systems to detect, characterize, and image SNM. In this presentation, I will discuss these challenges and the recent advances in detector development, electronics, and algorithms that contribute to solving them. I will present recent results from experiments performed on plutonium at the JRC in Ispra, Italy and on uranium at the Los Alamos National Laboratory. In addition, a description of our Monte Carlo code systems will be provided, with particular emphasis on the physics of emission of correlated neutrons and gamma rays from fission events. Finally, I will describe the neutron and gamma ray dual-particle imaging detection system developed at UM to pinpoint the location of SNM.