I need to know the practical applications of the absorption of gamma rays in materials.
Most of the time, it's shielding. In other words, gamma rays (an neutrons) are highly penetrating and are very damaging to living tissue, so the typical use of materials for attenuating gamma radiation is shielding.
Speaking of Gamma Rays,
Just got an e-mail from the ESO's Very Large Telescope about a faint gamma-ray burst detected last Thursday that is the signature of the explosion of the earliest, most distant known object in the Universe.
There are three distinct regions of gamma ray absorption; a)Photoelectric effect (usually roughly below the binding energy of the 1s shell electrons in nuclei), c) above the pair production threshold (above 1.02 MeV) with some Z dependence, and b) (between a )and c)) Compton scattering.
this smells homework... "I need"
I can give you a practical use: X-ray images
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