Re: Self-Absorption Effects on Air Filters

[William Lorenzen <LORENZEN_W@A1.TCH.HARVARD.EDU>]

I have found different results.  I have seen 30% or more self absorption for 
U-238 alpha particles on glass fiber filter paper.  Some other factors are the 
type of glass fiber (the brands do differ); the flow rate used in sampling 
(which tends to drive the depth of burial into the filter paper); the energy of 
the alpha particle; the loading of the filter paper (the more "dirt" the more 
self attenuation).

These are some.  Sorry I do not have a specific reference to cite.

William A. Lorenzen
Children's Hospital
Boston, MA

lorenzen_w@a1.tch.harvard.edu

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