assignment - -1 X-rays are emitted from a parallel ray...

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Consider a parallel beam X ray source which outputs the following energy distribution  Number of Photons Photon Energy 10 6   10 keV   10 5   20 keV   10 4   30 keV   10 3   40 keV   10 2   50 keV   The X-rays travel through a mixture of soft tissue and bone. At these frequencies, these tissues  have the following attenuation coefficients:  Photon Energy Attenuation Coefficient  of Bone Attenuation Coefficient  of Soft Tissue 10 keV   2.7 cm -1    0.6 cm -1    20 keV   0.43 cm -1    0.25 cm -1    30 keV   0.28 cm -1    0.20 cm -1    40 keV   0.24 cm -1    0.19 cm -1    50 keV   0.20 cm -1    0.18 cm
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Unformatted text preview: -1 X-rays are emitted from a parallel ray source toward the target in figure 1. Measurements A and B represent the energy of photons captured after travelling through the target. The contrast is ( A − B ) / B. Figure 1: X-ray source, target and detector o (5 Marks) Two different objects are measured. Object #1 has d 1 =9 cm, and d 2 =1 cm. Object #2 has d 1 =4 cm, and d 2 =1 cm. What is the contrast for each object? o (5 Marks) Briefly explain the effect of "beam hardening" in your result?...
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This note was uploaded on 06/18/2011 for the course PHYSICS PHYS425 taught by Professor Phys during the Spring '11 term at Abu Dhabi University.

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