Matthew Anderson Jessee

Matthew A Jessee

Senior R&D Staff, Power Reactor Modeling, Acting Group Lead

Dr. Matthew A. Jessee is a Senior Research and Development staff member in the Power Reactor Modeling Group of the Nuclear Energy and Fuel Cycle Division at Oak Ridge National Laboratory. His research interests include methods and software development in lattice physics analysis, Monte Carlo analysis, multigroup cross section processing, sensitivity analysis, uncertainty quantification, parameter estimation, and reduced order modeling for challenging reactor physics and radiation transport applications.

Since 2019, Dr. Jessee has served as the Reactor Physics technical area lead in the DOE-NE Nuclear Energy Advanced Modeling and Simulation (NEAMS program), where he coordinates the development of reactor physics codes (Griffin, MPACT, and Shift) across DOE laboratories. He is an active developer of the Shift Monte Carlo code for enabling reference solution capabilities and two-step neutronics calculations with Shift and Griffin.

Dr. Jessee is a senior code developer of the SCALE Code System. His primary role is the development of the Polaris lattice physics code in SCALE Code System. Introduced in SCALE 6.2 in April 2016, Polaris is an easy-to-use lattice physics capability for light water reactor assemblies.  Polaris uses advanced calculation methods for performing lattice physics analysis, including the embedded self-shielding method for cross section processing, a method for the characteristics transport solver, the ORIGEN depletion solver, and automated assembly geometry processing based on simplified user input format.

Dr. Jessee is the 2023 Division Chair of the Reactor Physics Chair of the American Nuclear Society. He completed his PhD in Nuclear Engineering at the North Carolina State University in 2008, where he was funded through the Naval Nuclear Propulsion Fellowship. He completed his Masters of Nuclear Engineering (MNE) at North Carolina State University in 2005 and his BS in Nuclear Engineering at the University of Tennessee in 2003.