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Nine elementary schools in Maine were examined to track the release of 222Rn and to determine the transfer coefficient from water into air. Water-use simulations were performed by running sinks and sprayers for 1 h in a kitchen. The 222Rn in air was measured over 24 h throughout the school. The subsequent release of 222Rn into the kitchen air was measured to be greater than the EPA action level of 0. 15 Bq L-1 (4 pCi L-1), but negligible concentrations of 222Rn were found in adjacent classrooms. In two schools, more than 10 222Rn-in-air detectors were placed throughout the kitchen and showed a three-fold spatial concentration variation. During the hour-long simulations, the 222Rn in water concentration was measured periodically, and many of the schools showed an Increase in the 222Rn concentration in water before remaining constant. These measured variations suggest that multiple detectors are needed to accurately measure waterborne 222Rn in air, and multiple delayed measurements of 222Rn dissolved in water are needed to obtain a representative groundwater sample.

The article focuses on the water testing laboratory in Maine. It provides measurements of radon in water for the public. While, no known national intercomparison program exists to verify the accuracy of the laboratories. It is said that radon is a naturally occurring gas that can be found underground in soils and rock and would dissolve in ground water. On the other hand, the State of Maine Radiation Control Program sanctioned an intercomparison study for laboratories registered in Maine to measure radon in water. Of the laboratories who responded on the call, different methods have been presented and eight of which used the liquid scintillation method and others used the E-PERM method of measuring radon in water.

This study investigated the transfer coefficient of radon from water to air in kitchens and bathrooms for seven schools located in Maine. Simulations occurred in water use rooms containing multiple airborne radon detectors. Quantities measured included radon concentration in water (10-960 Bq L-1, 260–26,000 pCi L-1), air (0–3 Bq L-1, 0–80 pCi L-1), volume of water used, emissivities (0.04–0.98), and ventilation rates (0.012–0.066 min-1). Using these parameters provides the means for calculating the transfer coefficient and by which dose due to waterborne radon can be estimated in other schools. Transfer coefficient values calculated for kitchens and baths ranged from 9.6 × 10-6 to 2.0 × 10-2. Multiple detectors showed that the radon concentration varied throughout a room. These measurements represent the first of this type to be done in schools in Maine. [ABSTRACT FROM AUTHOR]

Neutrinoless double-beta decay searches play a major role in determining the nature of neutrinos, the existence of a lepton violating process, and the effective Majorana neutrino mass. Neutrino oscillation experiments have demonstrated that neutrinos have mass but the ordering of the masses and the absolute mass scale are yet unknown. The rate of neutrinoless double-beta decay is proportional to the effective Majorana neutrino mass and when combined with the global neutrino oscillation experiments would set the absolute mass scale. The neutrinoless double-beta decay process also requires the neutrino to be indistinguishable from the anti-neutrino and lepton number violation. There has been significant experimental progress to date utilizing a range of techniques to detect double-beta decay. Within the next five years, several experiments will be able to confirm or refute a recent controversial claim of neutrinoless double-beta decay. In 5-10 years, double-beta decay experiments will probe the exciting mass region indicated by atmospheric neutrino mixing. [ABSTRACT FROM AUTHOR]

Background: Experiments designed to study rare processes, such as neutrinoless double-β decay (Ovββ), are crucial tests for physics beyond the standard model. These experiments rely on reducing the intrinsic radioactive background to unprecedented levels, while adequately shielding the detectors from external sources of radioactivity. Purpose: The purpose of this work is focused on understanding the background rates from neutron interactions in Cu shielding in regions around the Q values of many candidate Ovββ decay isotopes, as well as providing data for benchmarking Monte Carlo simulations of background events. Methods: Using the broad-spectrum neutron beam at Los Alamos Neutron Science Center, we have measured γ rays emitted from inelastic neutron scattering on natCu. Results: We extracted the level cross sections from the γ-production cross section for 46 energy levels in natCu. These level cross sections were compared with the available experimental data, as well as the ENDF/B-VII evaluation for discrete levels. Conclusions: For energy levels above 2 MeV we found significant discrepancies between the suggested level cross sections for both nuclei and our data. We found reasonable agreement between our measurement and the ENDF/B-VII evaluation for the total neutron inelastic cross section in 63Cu. Our measurement of the total neutron inelastic scattering cross section in 65Cu was 30% lower than the ENDF/B-VII evaluations, which we attribute to unobserved transitions in 65Cu. Furthermore, we found that the implementation of the ENDF/B-VII evaluation in simulations did not properly model the decay properties of the nucleus to the degree necessary for estimating backgrounds in rear-event searches. Finally, we examined the potential implications of our measurements on Ovββ measurements and found that many of the commonly studied Ovββ isotopes had Q values below the cutoff for ENDF/B-VII evaluated discrete levels in either Cu nucleus. [ABSTRACT FROM AUTHOR]

Background: Neutron-induced reactions are a significant concern for experiments that require extremely low levels of radioactive backgrounds. Measurements of y-ray production cross sections over a wide energy range help to predict and identify neutron backgrounds in these experiments. Purpose: The purpose of this experiment is to determine partial y-ray production cross sections for neutron-induced reactions in natural neon. Methods: The broad spectrum neutron beam at the Los Alamos Neutron Science Center (LANSCE) was used for the measurement. Gamma rays from neutron-induced reactions were detected using the GErmanium Array for Neutron Induced Excitations (GEANIE). Results: Partial y-ray cross sections were measured for the first excited-state transitions in 20Ne and 20Ne. The measured cross sections were compared to the TALYS and CoH3 nuclear reaction codes. Conclusions: These are the first experimental data for (n, n') reactions in neon. In addition to providing data to aid in the prediction and identification of neutron backgrounds in low-background experiments, these new measurements will help refine cross-section predictions in a mass region where models are not well constrained. [ABSTRACT FROM AUTHOR]

Background: Neutron-induced backgrounds are a significant concern for experiments that require extremely low levels of radioactive backgrounds such as direct dark matter searches and neutrinoless double-β) decay experiments. Unmeasured neutron scattering cross sections are often accounted for incorrectly in Monte Carlo simulations. Purpose: The purpose of this article is to determine partial γ-ray production cross sections for (n,xnγ) reactions in natural argon for incident neutron energies between 1 and 30 MeV. Methods: The broad-spectrum neutron beam at the Los Alamos Neutron Science Center (LANSCE) was used used for the measurement. Neutron energies were determined using time of flight, and resulting γ rays from neutron-induced reactions were detected using the GErmanium Array for Neutron Induced Excitations (GEANIE). Results: Partial γ-ray cross sections were measured for six excited states in 40Ar and two excited states in 39Ar. Measured (n,xnγ) cross sections were compared to the TALYS and CoH3 nuclear reaction codes. Conclusions: These new measurements will help to identify potential backgrounds in neutrinoless double-β decay and dark matter experiments that use argon as a detection medium or shielding. The measurements will also aid in the identification of neutron interactions in these experiments through the detection of γ rays produced by (n,xnγ) reactions. [ABSTRACT FROM AUTHOR]