Aerosol-size distribution of radon daughter 218 Po in the accelerator tunnel air

Aerosol-size distributions of 218 Po were determined for the accelerator tunnel air sampled during machine operation and for the basement air of a concrete building, where the number and the size distribution of non-radioactive aerosols are greatly different from each other. The 218 Po distributions depended very much on the size distributions of ambient non-radioactive aerosols, and could be well explained by an attachment model of 218 Po to ambient non-radioactive aerosols.