Optimal Background Attenuation for Fielded Radiation Detection Systems

Conference · Sun Oct 29 04:00:00 EST 2006

DOI:https://doi.org/10.1109/NSSMIC.2006.356156· OSTI ID:990154

Robinson, Sean M; Kaye, William R; Schweppe, John E; Siciliano, Edward R

Radiation detectors are often placed in positions difficult to shield from the effects of terrestrial background. This is particularly true in the case of Radiation Portal Monitor (RPM) systems, as their wide viewing angle and outdoor installations make them susceptible to terrestrial background from the surrounding area. A low background is desired in most cases, especially when the background noise is of comparable strength to the signal of interest. The problem of shielding a generalized RPM from terrestrial background is considered. Various detector and shielding scenarios are modeled with the Monte-Carlo N Particle (MCNP) computer code. Amounts of nominal-density shielding needed to attenuate the terrestrial background to varying degrees are given, along with optimal shielding geometry to be used in areas where natural shielding is limited, and where radiation detection must occur in the presence of natural background. Common shielding solutions such as steel plating are evaluated based on the signal to noise ratio and the benefits are weighed against the incremental cost.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 990154
• Report Number(s): PNNL-SA-52472; 400904120
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
ATTENUATION
BACKGROUND NOISE
BACKGROUND RADIATION
COMPUTER CODES
MONITORS
MONTE CARLO METHOD
Monte-Carlo N Particle (MCNP) computer code
OUTDOORS
PLATING
RADIATION DETECTION
RADIATION DETECTORS
RADIATIONS
Radiation Portal Monitor (RPM) systems
SHIELDING
SHIELDS
SIGNAL-TO-NOISE RATIO
STEELS
terrestrial background