Gamma Rays Absorbed by High Density Material

Gamma rays are better absorbed by materials with high atomic numbers and high density, such as tungsten alloy material. Although neither effect is important compared to the total mass per area in the path of the gamma ray. For this reason,lead shield is only modestly better (20–30% better) as a gamma shield, than an equal mass of another shielding material such as aluminium, concrete, water or soil, lead's major advantage is not in lower weight, but rather its compactness due to its higher density. Therefore, tungsten alloy material is better in its high density,good radiation absorption, etc.

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