Deterministic Transport Methods for the Simulation of Gamma-Ray Spectroscopy Scenarios

Conference · Thu Nov 30 23:00:00 EST 2006

DOI:https://doi.org/10.1109/NSSMIC.2006.356224· OSTI ID:1000841

Smith, Leon E; Gesh, Christopher J; Pagh, Richard T; McConn, Ronald J; Ellis, J E; Kaye, William R; Meriwether, George H; Miller, Erin A; Shaver, Mark W; Starner, Jason R; Valsan, Andrei B; Wareing, Todd A

Radiation transport modeling methods used in the radiation detection community fall into one of two broad categories: stochastic (Monte Carlo) and deterministic. Monte Carlo methods are typically the tool of choice for simulating gamma-ray spectrometers operating in homeland and national security settings (e.g. portal monitoring of vehicles or isotope identification using handheld devices), but deterministic codes that discretize the linear Boltzmann transport equation in space, angle, and energy offer potential advantages in computational efficiency for many complex radiation detection problems. This paper describes the development of deterministic algorithms for simulating gamma-ray spectroscopy scenarios. Key challenges include: formulating methods to automatically define an energy group structure that can support modeling of gamma-ray spectrometers ranging from low to high resolution; combining deterministic transport algorithms (e.g. ray-tracing and discrete ordinates) to mitigate ray effects for a wide range of problem types; developing efficient and accurate methods to calculate gamma-ray spectrometer response functions from the deterministic angular flux calculations. The software framework aimed at these challenges is described and results from test problems that compare deterministic and Monte Carlo approaches will be provided.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1000841
• Report Number(s): PNNL-SA-52503; 400904120
• Country of Publication: United States
• Language: English

Related Subjects

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEFENSE
99 GENERAL AND MISCELLANEOUS
ALGORITHMS
BOLTZMANN EQUATION
COMPARATIVE EVALUATIONS
COMPUTERIZED SIMULATION
DISCRETE ORDINATE METHOD
EFFICIENCY
GAMMA SPECTROMETERS
GAMMA SPECTROSCOPY
MONITORING
MONTE CARLO METHOD
NATIONAL SECURITY
RADIATION DETECTION
RADIATION TRANSPORT
RESOLUTION
RESPONSE FUNCTIONS