unit 1- bushong chapter 7 Flashcards
what is the target material use in x-rays?
tungsten
x-rays are produced how?
interaction between electrons & the target
what are incoming electrons called?
incident electrons
the incedent electron travel in what direction?
from cathode striking the anode
what are the name of the two x-rays produced?
bremsstrahlung & characteristic
most of the interaction between lectrons and the anode is what?
heat
heat is produced through the excitation of which electrons?
outer shell
what two things doesnot happen in heat production?
the electron is not removed & the atom is not ionized
the outer shell electrons are raised to a higher energy state then returns back to normal releasing what kind of radiation (heat)?
infrared
what percentage of incident electrons are converted to heat?
99%
as energy icreases, efficiency does what?
increases
what is the formula for kinetic energy?
1/2mv2
what determines kinetic energy?
mass & velocity
how can we control velocity?
by changing kVp
what is Brems radiation called?
breaking radiation
for brems, the incident electron interact with what?
the electric field of the nucleus
when is the x-ray produced in a brems?
when the electron reaches the electric field of the nucleus, slows down & changed directions
brems production can occur at any energy up to the max what?
kVp
emissions are exactly the difference in the electrons what?
entering & exiting energy
in characteristic radiation, incident electron interacts with what? knocking an electron out of orbit.
inner shell - K shell
when an electron is knocked off the inner shell, what happens?
a hole is created on the K-shell so an electron from another shell will drop down to fill that hole
when is the character x-ray produced?
when the electron moves from shell to shell
what KeV is character x-rays produced at?
69, 69.5, 70
can other shells produce character x-rays?
yes but their energies are so low theu are of no diagnostic valve
what does spectrum refer to?
the range of energies produced
name the two spectrums
continuous & discrete
continuous refers to what?
curved portion of brems x-rays
discrete refers to what?
the straight vertical line at 70kV referring to the characteristic x-rays
what 5 things affect the emission spectrum?
mA, kVp, filtration, target material, and voltage waveform
