SUBJECT: Ph.D. Dissertation Defense
BY: Luke Maloney
TIME: Thursday, June 25, 2020, 11:00 a.m.
PLACE:, online
TITLE: Characterization of Algorithms and Performance of a Fine-Resolution Active Interrogation System
COMMITTEE: Anna Erickson, Chair (NRE)
CK Chris Wang (NRE)
Steven Biegalski (NRE)
Nolan Hertel (NRE)
Paul Rose (ORNL)
Rongxiao Zhang (Dartmouth-Hitchcock Medicine)


Dense scintillators are typically used in cargo radiography applications, due to their high efficiency for detecting gamma and x-rays. In this work, measurements validating a modeled system implementing quartz Cerenkov radiators and LYSO scintillator crystals are presented and discussed. The system implements silicon photomultipliers for light collection and has a uniquely engineered design which minimizes crosstalk between imaging elements. These design parameters necessitate an approach to image reconstruction algorithm design incorporating the geometric parameters, radiation energy information, raw count intensity, and object staging available from the system. Image metrics including spatial resolution and signal-to-noise ratio are discussed, and image-domain postprocessing is used as a knowledge-based technique for data regularization.