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arXiv · 1712.04777

Airborne gamma-ray spectroscopy for modeling cosmic radiation and effective dose in the lower atmosphere

Abstract

In this paper we present the results of a $\sim$5 hour airborne gamma-ray survey carried out over the Tyrrhenian sea in which the height range (77-3066) m has been investigated. Gamma-ray spectroscopy measurements have been performed by using the AGRS_16L detector, a module of four 4L NaI(Tl) crystals. The experimental setup was mounted on the Radgyro, a prototype aircraft designed for multisensorial acquisitions in the field of proximal remote sensing. By acquiring high-statistics spectra over the sea (i.e. in the absence of signals having geological origin) and by spanning a wide spectrum of altitudes it has been possible to split the measured count rate into a constant aircraft component and a cosmic component exponentially increasing with increasing height. The monitoring of the count rate having pure cosmic origin in the >3 MeV energy region allowed to infer the background count rates in the $^{40}$K, $^{214}$Bi and $^{208}$Tl photopeaks, which need to be subtracted in processing airborne gamma-ray data in order to estimate the potassium, uranium and thorium abundances in the ground. Moreover, a calibration procedure has been carried out by implementing the CARI-6P and EXPACS dosimetry tools, according to which the annual cosmic effective dose to human population has been linearly related to the measured cosmic count rates.

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Marica Baldoncini, Matteo Albéri, Carlo Bottardi, Brian Minty, Kassandra G. C. Raptis, Virginia Strati, Fabio Mantovani. 2017-12-13. Airborne gamma-ray spectroscopy for modeling cosmic radiation and effective dose in the lower atmosphere. https://doi.org/10.1109/tgrs.2017.2755466

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