Electric charge spectrum of recoiling 218Po

Abstract The chemical and physical properties of a radioactive nanometric aerosol are important in determining its behaviour in indoor atmospheres and play a major part in determining its potential health effects. In a well defined experimental system, mass spectrometry coupled to the Time-of-Flight technique, we measured the electric charge of 218 Po at the end of its recoil path. The charge distribution of the recoiling 218 Po is mainly neutral and singly charged with a very small multicharged fraction. In case of radon progeny embedded in solid matter this one can play a major role in the surface ionisation processes versus electron and ion emission induced by the passage of the alpha recoils through the surface.