Question

Which x-ray beam characteristic is reduced by adding aluminum filtration?

A. Energy of the x-ray beam.
B. Half-value layer.
C. Quantity of x-rays.
D. X-ray beam quality.

Answer 1

Adding aluminum filtration to an x-ray beam reduces the quantity of x-rays, as it preferentially absorbs low-energy photons more than high-energy photons, decreasing the number of photons in the beam.

Step-by-step explanation:

When aluminum filtration is added to an x-ray beam, it reduces the quantity of low-energy x-rays more than the high-energy x-rays. This is because the added aluminum preferentially absorbs the lower energy photons, which are more prone to interaction with matter due to their higher cross-section for photoelectric absorption. The higher-energy photons, which are more likely to undergo Compton scattering, are less affected by the filtration and remain in the beam to a greater extent. Therefore, the overall effect of adding aluminum filtration is to 'harden' the x-ray beam by increasing the average energy of the photons that make it through and to decrease the number of photons, which means the quantity of x-rays is reduced.