Electrostatic precipitator collection efficiency studies using atmospheric radon progeny as aerosol analogs for nuclear explosion radionuclides.

Electrostatic precipitation (ESP) is an attractive low-powered collection mechanism for mobile and fixed aerosol detection of radionuclides (RNs) for Nuclear Explosion Monitoring (NEM). Aerosol samplers deployed in the International Monitoring System use a blower to draw air through a filter media to collect particulates. ESP-based samplers collect aerosols without a filter, which can greatly increase volumetric flow capacity per watt of power consumed.

Investigating the detection of underground nuclear explosions by radon displacement.

A novel approach is proposed to detect underground nuclear explosions (UNEs) through the displacement of natural radon isotopes (Rn and Rn). Following an explosion, it is hypothesized that the disturbance and pressurization of the sub-surface would facilitate the movement of radon from the depth of the UNE towards the surface resulting in increased soil gas activity. The resulting signal may be magnified by a factor of 2.

Recent Bremsstrahlung-based assays of Pb in lead and comments on current availability of low-background lead in North America.

Low-background lead for radiation measurement shielding is often assayed for Pb to ensure acceptable backgrounds. Samples of lead assayed with a germanium spectrometer calibrated for bremsstrahlung-based assay of Pb provide a view into the Pb content of commercial lead in the U.S.

PRex: An Experiment to Investigate Detection of Near-field Particulate Deposition from a Simulated Underground Nuclear Weapons Test Vent.

A radioactive particulate release experiment to produce a near-field ground deposition representative of small-scale venting from an underground nuclear test was conducted to gather data in support of treaty capability development activities. For this experiment, a CO2-driven "air cannon" was used to inject (140)La, a radioisotope of lanthanum with 1.7-d half-life and strong gamma-ray emissions, into the lowest levels of the atmosphere at ambient temperatures.

Using Atmospheric Dispersion Theory to Inform the Design of a Short-lived Radioactive Particle Release Experiment.

Atmospheric dispersion theory can be used to predict ground deposition of particulates downwind of a radionuclide release. This paper uses standard formulations found in Gaussian plume models to inform the design of an experimental release of short-lived radioactive particles into the atmosphere. Specifically, a source depletion algorithm is used to determine the optimum particle size and release height that maximizes the near-field deposition while minimizing both the required source activity and the fraction of activity lost to long-distance transport.

Optical design considerations for efficient light collection from liquid scintillation counters.

Liquid scintillation counters measure charged particle-emitting radioactive isotopes and are used for environmental studies, nuclear chemistry, and life science. Alpha and beta emissions arising from the material under study interact with the scintillation cocktail to produce light. The prototypical liquid scintillation counter employs low-level photon-counting detectors to measure the arrival of the scintillation.