Geometric Efficiency Is Defined
A)as the Ratio of the Number $\mu$

question 21

Multiple Choice

Geometric efficiency is defined

• A)as the ratio of the number of detected events to the number of source emissions.
• B)as the fraction of emitted photons (gamma or x-rays) that hit the detector; it depends on the detector configuration and its distance from the source.
• C)as the fraction of gamma rays that are detected when they hit the detector; it depends on the thickness (t) and attenuation coefficient (\(\mu\)) of the detecting material.
• D)as the amount of blurring that is produced by an imaging system, characterized by point spread function and line spread function.

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