Dr. Paul Hausladen

Starting about a decade ago, Oak Ridge National Laboratory (ORNL) developed a series of position-sensitive fast neutron detectors based on fast organic scintillators. The development of these position-sensitive detectors enabled a new generation of fast-neutron imaging instruments and techniques with sufficient resolution to give new capabilities relevant to safeguards and nuclear material accountancy.  Toward this end, ORNL has built and demonstrated a number of passive and active fast-neutron imagers and techniques, including:

• A fast neutron transmission imager (based on the associated-particle technique) that requires no shielding or collimation, and can simultaneously image the distribution of fissile and hydrogenous material
• A fast neutron/thermal neutron imager (based on the coded aperture technique) that images sources in its surroundings
• A proof-of-concept fast neutron radial collimator imager capable of resolving individual plutonium-MOX fuel pins in an assembly via their neutron emanations

This talk will describe the position-sensitive detectors, the imaging systems they have enabled, and highlights of a number of measurement campaigns inspecting objects containing nuclear materials.

Bio

Dr. Paul Hausladen is a Distinguished Scientist in the Nuclear Material Detection and Characterization Group at Oak Ridge National Laboratory.  Dr. Hausladen received a B.A. in physics from Williams College and a Ph.D. in physics from the University of Pennsylvania.  In his formative years as an experimental nuclear physicist, he performed fundamental nuclear structure measurements on nuclei far from stability and used nuclear techniques to perform ultra-trace analysis (such as ¹⁴C dating).  Now Dr. Hausladen specializes in the use of detectors and characterization techniques that employ fast neutrons and either coincidence techniques, imaging, or both ⎯ primarily for the purpose of characterizing nuclear materials.  In particular, Dr. Hausladen has developed associated-particle imaging detectors and techniques enabling transmission imaging without collimation, induced-fission imaging to quantify fissionable materials, and scatter imaging to image the hydrogenous materials in inspected objects.  Dr. Hausladen also led development and demonstration of passive fast neutron imaging via the coded aperture technique.  At present, Dr. Hausladen is beginning a project to apply fast neutron imaging techniques for the purpose of counting fuel pins in spent nuclear fuel.