Chapter 8 Notes Flashcards
x-ray photons are produced when
high-speed electrons from the cathode strike an anode target
the greater the mass or speed of the incident electrons
the greater the quality (energy) and quantity (number) of photons produced
what are the two target interactions that produce x-ray photons
bremsstrahlung (brems) and characteristic interactions
what percent of the total kinetic energy of the incident electrons produces interactions
less than 1%
what percent of the kinetic energy of the incident electrons is converted to heat
99%
brems interactions occur when
the incident electron interacts with the force field of the nucleus; causes electron to brake and then diverts its course
the photon energy from a brems interaction is
the difference between the entering and exiting kinetic energy of the electron
characteristic interactions occur when
the incident electron interacts with an inner-shell electron; an electron hole is created, making the atom unstable; causes cascade effect
the photon energy of a characteristic interaction is
difference between the binding energy of the outer and inner shells
most photons are produced by what interaction
bremsstrahlung interactions
an x-ray emission spectrum graph illustrates what
relationship between the two target interactions within the primary beam
average primary beam photon has a keV energy of only about _____ percent of the kVp
30-40%
changing kVp changes what
the quality (energy) of electrons striking the target; changes the number of higher-energy photons and the amplitude of the emission spectrum graph
bremsstrahlung makes up what percent of diagnostic x-rays
> 90%
the closer the incident electron gets to the nucleus
the more it brakes and changes direction
the x-axis on the x-ray spectrum represents what
photon energy (keV)
the y-axis on the x-ray spectrum represents what
intensity (number of photons)