Compton
What is Compton Scattering?
An incident photon that interacts with outer shell, loosely bound electron and ejects it.
What are two types of Coherent Scatter?
Thompson and Rayleigh
What would decrease the chance of a Photoelectric interaction?
An increase in photon energy.
What results in "pair" of electrons?
Negatron and Positron.
What affect does kVp have on image quality?
kVp effects contrast.
What is the difference between Coherent and Compton scatter?
No ionization take place in Coherent, In Compton ion pairs are formed.
At what energy level does coherent scattering occur?
Occurs with x-rays having energy below 10KeV.
When does Photoelectric Absorption occur?
Photoelectric Absorption is most likely to occur in elements with higher Z (atomic) number.
What does the incident photon interact with doing Pair Production?
The Nucleus absorbed the incident photon and causes it to lose all energy.
As kVp increases, what happens to photoelectric absorption?
It decreases the probability of PE absorption.
How long would a recoil electron travel?
Until it fills a vacancy in another atom.
What is the result of Coherent Scattering?
It is change in direction of the x-ray without a change in its energy.
What happens to the incident photon?
It is totally absorbed by the patient.
What energy level is required for a photodisintegration to occur?
10 MeV or greater.
What happens when photo electric absorption predominates?
Resulting image will have a short scale contrast.
How is an Incident Photon Energy distributed?
It is distributed between a recoil electron and a scatter photon.
How would an atom stabilize itself?
It will stabilize itself by releasing a photon equal in energy to an incident photon, BUT in a different direction.
When will a Photoelectric absorption most likely occur?
When an incident photon energy and inner shell electron binding energy are close to each other.
What does the nucleus release during photodisintegration?
What happens when Compton interactions predominate?
Results in the image having a long scale contrast.
why does the scattered photon always have a longer wavelength than the incident photon?
Since the scattered x-ray photon has less energy, it has a longer wavelength and less penetrating than the incident photon
What percentage of interactions result in Coherent scatter?
about 5%.
What is the Photoelectron energy equation?
Ei = Eb + Eke
What energy ranges does PE interaction absorption predominate?
25-45 keV produce by 40-70 kVp techniques.
X-rays can either interact with:
Entire atom, orbital electron, or nucleus of atom.