TEST 2 REVIEW RAD PROTECTION

Photoelectric and Compton

What are the 2 interactions which have a significant impact on the radiographic image

Backscatter

When a scattered photon is deflected toward the original source and is traveling in a direction opposite to the incident photon

Compton Scattering

During which interaction does backscatter occcur

High contrast/short scale

What type of radiographic contrast will result if the prevalent interaction is photoelectric absorption

Photoelectric Absorption

What interaction results when an x-ray photon interacts with an inner-shell electron

Photoeclectric Absorption

What interaction results in secondary radiation (characteristic radiation) being produced

Compton scattering

What interaction occurs when an x-ray photon interacts with a loosely bound outer-shell electron and CHANGES DIRECTION

Coherent Scattering

What interaction occurs between very low energy x-ray photons and matter, and does not ionize the atom

Low contrast/long scale

What type of contrast will result if the prevalent interaction is Compton Scatter

Pair production

Requires a photon with 1.02 MeV. Incident photon comes close to the nuclear field and loses all its energy. The energy is used to create 2 electrons

Photodisintegration

Requires 10 MeV. Incident photon strikes the nucleus and all its energy is absorbed by the nucleus and emits a nuclear fragment

Compton Scatter

Ei=Es+Eb+Eke defines the energy transfer in what interaction

True

T/F: When the angle of deflection of the scattered photon increases, more energy is imparted to the recoil electron and less energy remains with the scattered photon

Attenuation

The reduction in number of photons in beam resulting in loss of energy as it passes through matter

Matter

During the process of attenuation, the x-ray photon may interact with ________

K shell

Which atomic shell possesses the highest binding energy?

Increase, decrease

As the electron shells move further from the nucleus, total electron energies ____ and binding energies _____

Scatter

When x-ray photons interact with matter and change direction, the process is called _________.

Exits with less energy

If a photon interacts with matter and scatters, the photon _________.

Inner -shell

During a photoelectric absorption, a/an ____________ electron is ejected

Photoelectron

During photoelectric absorption, the ejected electron is called a/an ______________.

Secondary Radiation

During the photoelectric interaction, as an electron transfers from an outer shell to a vacant inner shell energy is released in the form of _____________________.

Increases

The probability of a photoelectric interaction increases dramatically as the atomic number ____________.

The same energy, the same frequency, and the same wavelength

During Coherent scattering, the scattered photon possesses _______________ as the incident photon.

Recoil Electron

The electron dislodged during Compton scattering is called the __________ .

Effect

The photon that exits the atom in a different direction after a Compton scattering is called the Compton ________.

Recoil electron and scattered electron

During the Compton scattering, the incident photon energy is divided between the ____________.

Radiation Fog

Unwanted densities caused predominately by scattered photons are called ___________ .

Compton Scatter

In the human body, ______________ is the predominant interaction through most of the diagnostic x-ray range

Annihilation Reaction

In which process is matter converted back to energy

Characteristic cascade

The process of each shell filling lower shells with a corresponding emission of photons

Compton Scattering

Main source of occupational exposure

Coherent

This interaction occurs below the usual energy range for diagnostic x-ray

Compton

This interaction increases with increases in kVp

Incident photon energy
atomic number of matter
the difference between binding energy & shell level

The likelihood of one interaction occurring over another varies depending on ___________

Photoelectric

This interaction is the main source of patient dose

1.0 Al/Eq

What filtration thickness would result in the lowest entrance skin exposure dose to the patient

N

Out of N, K, L, and M, which level possesses the highest total energy

Barium

Out of Barium, Hydrogen, Carbon, and Oxygen, which element has the highest secondary radiation energies?

Greater energy is imparted to the recoil electron

What happens as the angle of deflection of a scattered photon is increased from 0-180 degrees

Are absorbed by the patient

In general, low energy photons _________

During _____ scattering, no energy is transferred in the interaction

Coherent

Diagnostic

photon interactions that are most common with orbital electrons are found in the ______ x-ray range

positive +

what is the charge of the nucleus

negative energy

shell electrons possess this kind of energy

k shell

energies in what shell are highest?

binding

shell electrons possess this kind of energy

energy

how photons interact will depend on the _____ of the photon

scattering

process when x-ray photons interact and change direction

interactions

there are 5 types of these between x-rays and matter

nucleus

very high energy photons (radiation therapy) are capable of interacting with _____ of an atom

photo disintegration

pair production and __________ occur only at very high photon energy ranges

atomic

elements with high _____ numbers have more tightly bound k-shell electrons

negative -

electron charge is what?

increase

with each successive shell, total electron energies _______

absorption

all of the energy of the phone is transferred to matter and the photon no longer exists

decrease

with each successive shell, binding energies _______

matter

the likelihood of one interaction occurring over another is dependent on the incident photon’s energy and the atomic number of the what?

low energy photons

filtration is the process of eliminating undesirable ____ by the insertion of absorbing materials to the primary beam

increase

as tubes age they cause a _______ in the inherent filtration

removing low energy photons

filtration affects patient dose by ____

aluminum, copper, glass

what materials are used as a filter?

half value layer, HVL

the amount of material that will reduce the intensity of the primary beam to one half its original value is the ______

Al/Eq

the filtration can be expressed in terms of _____

hardening

filtration is sometimes called _____ the beam because it removes the low energy photons

photoelectric

when an xray photon with a slightly greater energy than a binding energy of the inner shell electron interacts with that inner shell electron, the following interaction results:

Compton scatter

which of the following interactions with matter results in a radiograph with a lower contrast? Smaller differences between densities more gray shades?

characteristic cascade occurs

when an electron from an outer shell fills a vacancy in an inner shell _______.

photoelectric

which interaction ejects an electron that travels with kinetic energy that is equal to the difference between the incident photon AND the binding energy of the inner shell electron?

photoelectric

which of the following interactions with matter results in a radiograph processing high contrast? great differences in density, black and white