528 Tables 644 and 645 



RADIOACTIVITY 



TABLE 644. — Effective Range of Beta Particles from RaE in a Few Elements 



(After Gray-Douglas. Taken from Kovarik, McKeehan, Nat. Res. Council Bull. 51, 1929.) 



Element C Al Cu Sn Pb 



Effective range, g/cm 2 474 .460 .432 .395 .354 



TABLE 645. — Absorption of Characteristic Beta Particles in Air and C0 2 



(After Kovarik.) 



Smithsonian Tables 



