Pb shift in the aerosol size distributions

A recoil model established by Papastefanou and Bondietti (1987) which accounts for the 

the radon decay products are defined in terms of their atmospheric disttibutions at some time during their life  

A is the fraction of the total Po that attaches to any aerosol particle before it decays to 214pb  

Ri is the fraction of the Pb that, through recoil, is lost from aerosol particle size interval i following 2i Po decay  

---