Characteristic Radiation in Tungsten Targets

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Characteristic Radiation in Tungsten Targets
Shell of electrons Binding energy L Char M Char N Char O Char P Char Eff X-ray Energy
K 2 69 57.4 66.7 68.9 69.4 69.5 69
L 8 12 9.3 11.5 12 12.1 12
M 18 3 2.2 2.7 2.8 3
N 32 1 0.52 0.6 0.6
O 12 0.1 0.08 0.1
P 2
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• In a tungsten target, at any kVp less than 69.5
  all x-rays are Brems.
• At 100 kVp, 85 of photons are Brems and 15 are
  characteristic
• Only 15 different energy levels are possible with
  characteristic production in tungsten tube.

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determine energy of electrons ? energy of X-ray
photons
determine number of electrons ? number of X ray
photons
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Photons entering the human body will either
penetrate, be absorbed, or produce scattered
radiation
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Where do X-rays come from ?
Atom of the target element
Characteristic X-ray
Nucleus
Bremsstrahlung
Electrons