511 keV photon attenuation in tungsten

Photon attenuation in elemental matters

For 0.5 MeV photon, [math]\mu / \rho = 0.1378~(cm^2/g)[/math], or [math]\mu_{en} / \rho = 0.0744~(cm^2/g)[/math]

[math]\frac{\mu}{rho}=0.1378\frac{cm^2}{g}[/math]

Tungsten density [math]{rho}=19.25 g/cm^3[/math]

so, [math]\mu = 2.65265/cm = 0.265265/mm[/math]

[math] I = I_0 e^{-\mu x}[/math] = intensity of light

if [math]I= \frac{I_0}{2}[/math]