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arXiv · 1712.04797

Exploring atmospheric radon with airborne gamma-ray spectroscopy

Marica Baldoncini·Matteo Albéri·Carlo Bottardi·Brian Minty·Kassandra G. C. Raptis·Virginia Strati·Fabio Mantovani
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Abstract

$^{222}$Rn is a noble radioactive gas produced along the $^{238}$U decay chain, which is present in the majority of soils and rocks. As $^{222}$Rn is the most relevant source of natural background radiation, understanding its distribution in the environment is of great concern for investigating the health impacts of low-level radioactivity and for supporting regulation of human exposure to ionizing radiation in modern society. At the same time, $^{222}$Rn is a widespread atmospheric tracer whose spatial distribution is generally used as a proxy for climate and pollution studies. Airborne gamma-ray spectroscopy (AGRS) always treated $^{222}$Rn as a source of background since it affects the indirect estimate of equivalent $^{238}$U concentration. In this work the AGRS method is used for the first time for quantifying the presence of $^{222}$Rn in the atmosphere and assessing its vertical profile. High statistics radiometric data acquired during an offshore survey are fitted as a superposition of a constant component due to the experimental setup background radioactivity plus a height dependent contribution due to cosmic radiation and atmospheric $^{222}$Rn. The refined statistical analysis provides not only a conclusive evidence of AGRS $^{222}$Rn detection but also a (0.96 $\pm$ 0.07) Bq/m$^{3}$ $^{222}$Rn concentration and a (1318 $\pm$ 22) m atmospheric layer depth fully compatible with literature data.

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Marica Baldoncini, Matteo Albéri, Carlo Bottardi, Brian Minty, Kassandra G. C. Raptis, Virginia Strati, Fabio Mantovani. 2017-12-13. Exploring atmospheric radon with airborne gamma-ray spectroscopy. https://doi.org/10.1016/j.atmosenv.2017.09.048

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