The study presented the relationship between sudden Natural Gamma Radiation (NGR) increases related to enhanced atmospheric electric fields. We pinpoint Thunderstorm Ground Enhancements (TGEs) as the primary source of abrupt and significant NGR spikes. These TGEs, which are transient, several-minute-long increases in elementary particle fluxes, originate from natural electron accelerators within thunderclouds. The more prolonged, yet less pronounced, increases in NGR, persisting for several hours, are attributed to the gamma radiation from radon progeny and enhanced positron fluxes. This radon, emanating from terrestrial materials, is carried aloft by the Near-Surface Electric Field (NSEF). To measure NGR at Aragats Mountain, we use an ORTEC detector and custom-built large NaI (Tl) spectrometers, employing lead filters to discriminate between cosmic ray fluxes and radon progeny radiation. Our analysis differentiates between radiation enhancements during positive and negative NSEF episodes. The resultant data provide a comprehensive measurement of the intensities of principal isotopes and positron flux during thunderstorms compared to fair weather conditions.
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http://dx.doi.org/10.1016/j.jenvrad.2024.107409 | DOI Listing |
Med Phys
January 2025
OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Germany.
Background: Patient-specific quality assurance (PSQA) is a crucial yet resource-intensive task in proton therapy, requiring special equipment, expertise and additional beam time. Machine delivery log files contain information about energy, position and monitor units (MU) of all delivered spots, allowing a reconstruction of the applied dose. This raises the prospect of phantomless, log file-based QA (LFQA) as an automated replacement of current phantom-based solutions, provided that such an approach guarantees a comparable level of safety.
View Article and Find Full Text PDFMed Phys
January 2025
Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, China.
Background: Online adaptive radiotherapy (OART) and rapid quality assurance (QA) are essential for effective heavy ion therapy (HIT). However, there is a shortage of deep learning (DL) models and workflows for predicting Monte Carlo (MC) doses in such treatments.
Purpose: This study seeks to address this gap by developing a DL model for independent MC dose (MCDose) prediction, aiming to facilitate OART and rapid QA implementation for HIT.
Int J Radiat Biol
January 2025
Department of Horticulture, Patuakhali Science and Technology University, Patuakhali, Bangladesh.
Purpose: The study focused on developing a rapid PCR-based detection method and employing gamma irradiation techniques to manage , aiming to produce brown rot-free export-quality potatoes. This initiative seeks to enhance potato exports from Bangladesh.
Materials And Methods: Samples of potato tubers and soil were collected from various commercially significant potato-growing areas, resulting in a total of 168 isolates from potato tubers and soil across 12 regions.
Clin Transl Radiat Oncol
March 2025
Smilow Center for Translational Research, Room 8-136, Univ of Pennsylvania, Perelman School of Medicine, 3400 Civic Center Blvd, Bldg 421, Philadelphia, PA 19104, USA.
Cardiac stereotactic body radiotherapy is a promising noninvasive treatment for patients with refractory ventricular tachycardia. With the aim to prove feasibility of a novel image guided radiotherapy and heart motion gating device, cardiac proton radiotherapy was performed using a porcine model. Using a novel adaptation of γ - H2AX tissue staining techniques, we have been able to localize a radiation beam in large animal tissue to assess targeting accuracy within a defined field.
View Article and Find Full Text PDFExp Astron (Dordr)
January 2025
Space Sciences Laboratory, University of California, Berkeley, 7 Gauss Way, Berkeley, 94720 CA USA.
We present an investigation into the effects of high-energy proton damage on charge trapping in germanium cross-strip detectors with the goal of accomplishing three important measurements. First, we calibrated and characterized the spectral resolution of a spare COSI-balloon detector in order to determine the effects of intrinsic trapping, finding that electron trapping due to impurities dominates over hole trapping in the undamaged detector. Second, we performed two rounds of proton irradiation of the detector in order to quantify, for the first time, the rate at which charge traps are produced by proton irradiation.
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