Innovative methodologies for the analysis of radon time series

Summary. — The present contribution is a part of a wide and detailed study on the long-term radon time series specific activity using novel methods of analysis with different aims: to extract the general trend; to evidence and distinguish endogenous and climatic dependences; to identify anomalies in order to show the correlation with geophysical phenomena; to forecast the original signal. Various examples of application of these methods are exhibited on radon time series collected in some Italian sites, in order to make a retrospective analysis to better study the existing correlation between anomalies and earthquakes. The results obtained from this study highlight the manifold capabilities of the proposed methods in the radon signal analysis, exploitable also for any kind of research framework that needs data analysis of time series.