RT Journal Article T1 A new efficiency calibration methodology for different atmospheric filter geometries by using coaxial Ge detectors A1 Barba Lobo, Alejandro A1 Bolívar Raya, Juan Pedro AB The study of the different pollutants present in atmospheric aerosols such as trace elements and radionuclides is essential to assess the air quality. To analyze the particulate matter (PM), atmospheric filters with different dimensions and geometries (rectangular, circular, slotted, and square filters) are usually employed. Regarding the pollutants existing in atmospheric aerosols, radionuclides are usually analyzed due to their multiple applications such as either in the environmental radiological control or as tracers of atmospheric processes. Therefore, this study aims to develop a new and general methodology to calibrate in efficiency coaxial Ge detectors to properly determine radionuclides present in the PM by gamma-ray spectrometry for several filter types. For this, granular certified reference materials (CRM) containing only natural radionuclides (²³⁸U-series, ²³²Th-series, and ⁴⁰ K) were selected. Several granular solid CRMs were chosen allowing us to reproduce the same PM deposition geometry and to assure the homogeneity of the added CRMs. These are the main advantages in relation to the typical methods that use liquid CRMs. Furthermore, for filters whose surfaces are relatively large, they were cut in several pieces and placed one on top of the other, achieving the same geometry than the PM deposited onto the filter. Then, the experimental full-energy peak efficiencies (FEPEs) were obtained for each energy of interest (Eγ) and they were fitted versus Eγ, finding a general FEPE function for each filter type. Finally, this methodology was validated for both natural and artificial radionuclides (from 46 to 1332 keV) by using different filter types employed in proficiency test exercises, obtaining |zscore|< 2 for all cases. PB Springer Science and Business Media LLC SN 1873-9318 SN 1873-9326 (electrónico) YR 2023 FD 2023 LK https://hdl.handle.net/10272/22153 UL https://hdl.handle.net/10272/22153 LA eng NO Barba-Lobo, A., & Bolívar, J. P. (2023). A new efficiency calibration methodology for different atmospheric filter geometries by using coaxial Ge detectors. In Air Quality, Atmosphere & Health. Springer Science and Business Media LLC. https://doi.org/10.1007/s11869-023-01336-x NO Funding for open access publishing: Universidad de Huelva / CBUA This research has partially funded by the projects of the Regional Government of Andalusia called “Treatment of acid leachates from phosphogypsum piles located at Huelva, and transport modelling of the released radionuclides” (Ref.: P20_00096) and “Valorization of inorganic wastes enriched in natural radioactivity for sustainable building materials” (Ref.: FEDER-UHU-202020); the project funded by the Spanish Nuclear Safety Council (CSN) “Radon exhalation from building materials; radiological impact and corrective measures” (Ref.: SUBV-4/2021); the project funded by the Spanish Ministry of Science, Innovation and Universities’ Research Agency “Development and optimization of a process for removing natural radionuclides in phosphogypsum leachates” (Ref.: PID2020-116461RB-C21); and the Project for Novel Principal Investigators “Quantitative study of the variables involved in the radon exhalation rate for granular solids; application to rafts of granular solid phosphogypsum” (Ref.: UHUPJ-00005–632). DS Repositorio Institucional de la Universidad de Huelva RD 12 jul 2026