A marginal process for radioactivity's betas
Comparison of bremsstrahlung and ionization electrons energy loss rates in a medium such as copper (Z = 29). The thickness of an absorber is usually expressed in grams per cm2. For beta electrons of radioactovity whose energy are generally less than 1 MeV, the contribution of bremsstrahlung - that increases with energy - is still small or marginal. This energy loss would be multiplied by 8 with heavy absorbers such as lead (Z = 82).