Question

Determining the Mass Attenuation Coefficient μ/ρ

N=N_o​e^{−(μ/ρ)(ρx)}

N is the number of counts per unit time (activity) after passing through an absorber of thickness x, N_o​ is the number of counts incident on the absorber per unit time, the quantity (μ/ρ) is the mass attenuation coefficient, ρx is the linear density in mg/cm^2mg/cm2 and ρ is the density of the absorber material in mg/cm^3mg/cm3. If we take the natural logarithm of both sides we obtain:

ln(N)=ln(N_o​)−(μ/ρ)(ρx)

QUESTION: What density thickness (px) would you need to reduce the intensity of radiation by 1⁄2? (Use 5.9 x 10^-5cm²/mg for (μ/ρ), the mass attenuation coefficient)

Answer 1