Analysis of gross alpha, gross beta activities and beryllium- 7 concentrations in surface air: their variation and statistical prediction model

Background: Measurement of gross , gross activities, and cosmogenic beryllium-7 (7Be) concentrations were made both daily and weekly during the years 2001- 2004 from samples of atmospheric aerosols filtered from the air at Tehran Nuclear Research Center (35 41' N) and Zahedan (28 29' N). Materials and Methods: Weekly aerosol samples were collected with the high-volume air samplers on cellulose filters to determine the 7Be contents of samples, using a semiconductor gamma spectrometer. Airborne dust samples were collected on daily basis on fiber glass filters and used to determine the gross and gross activities with automatic beta analyzer and a ZnS(Ag) counter, respectively. In this study, the concentration and meteorological data were used to determine models for gross , gross and 7Be. Results: The air concentrations of gross and gross activities and 7Be concentrations displayed lognormal distributions during the study period. Both and 7Be had maximum activity concentrations during warm mid-year months. Conclusion: The models can be used to estimate the part of the trend in gross and in 7Be levels that can be accounted for by-trends in local meteorology. There has been a satisfactory agreement between the results of the model and the measurements.