Effect of precipitation on the background levels of the atmospheric β- and γ-radiation

Results of experimental and theoretical studies of the responses of the β- and γ-radiation fields in the surface atmosphere to precipitation are presented. Most of the bursts of the β-radiation flux density and γ-radiation dose rate were found to coincide with periods of precipitation. However, the magnitude of bursts does not always correlate with the intensity of the precipitation. The following aspects were analyzed: the total duration of recorded bursts, the durations of the rises and recessions of the bursts, the form of the bursts and the dependence of the magnitude of the bursts on the altitude of the detector position. Results of a simulation of the impact of rainfall on the volume activity of the radon decay products and on the background levels of the atmospheric β- and γ-radiation were found to be in good agreement with the experimental data.