ABSTRACT
Lomnický stít, Slovakia, 2634 m above sea level, is known to be a place of extreme electric fields measured during thunderstorms and is thus a suitable place for thunderstorm-related ionising radiation research. We present one of the strongest Thunderstorm ground enhancements (TGE) ever detected, which occurred on 12 September 2021. The TGE was detected with the SEVAN detector and also with the new Georadis RT-56 large volume gamma spectrometer. In the paper, we present spectra of the TGE measured with the spectrometer as well as SEVAN coincidence data supplemented by the data from electric field mill.
ABSTRACT
The activity concentrations of Beryllium-7 ((7)Be), a naturally occurring radioisotope produced in the atmosphere, were measured in leaves of birch-trees, above-ground parts of grass, soil and rainwater in the mountain massive Kralicky Sneznik (the northeast of the Czech Republic, altitude about 750 m) in the years of 2005, 2006 and 2007. Dried and ground samples of the plants and soils, and water samples from wet deposition were used to determine the (7)Be content using a semiconductor gamma spectrometer. The (7)Be values ranged from 147.0 to 279.6 Bq kg(-1), from 48.7 to 740.8 Bq kg(-1), from 2.1 to 8.7 Bq kg(-1), and from 0.6 to 1.9 Bq kg(-1) in birch-tree leaves, grass samples, soils, and rainwater, respectively. Insignificant inter-annual variations but significant increase in the (7)Be activity concentrations during the spring and summer months were observed in birch-tree leaves and grass samples. The seasonal variation of the (7)Be concentrations in grass samples correlated (R(2) = 0.4663 and 0.6489) with precipitation. No similar correlation was found for (7)Be in birch-tree leaves. Beryllium-7 content in birch-tree leaves and in aerial parts of grass was mainly caused by direct transport of (7)Be from wet deposition into aerial parts of the observed plants.
