medical imaging quiz two

What happens to the probability of the photoelectric interaction when the photon energy increases

decreases

Which type of nuclear radiation has the shortest range in tissue?

Alpha radiation

A photon interaction most responsible for the prominence of bony anatomy on simulator films is the

Photo electric interaction

What do you know about photoelectric interactions?

Very important in diagnostic radiology

Low atomic number equals low probability

It transfers, all of its energy to the electrons

Leads to a character characteristic reaction

Basis for the lead apron

When the incident photo hits the inner shell electron it ejects it and the electrons from higher energy levels dropped to a lower level

A photon detected following a photoelectric interaction is most likely to be what type of x-ray

Characteristic x-ray

What happens in pair production annihilation reaction?

The incident electron interacts with the nucleus of the atom and produces a Megatron and a positron which each value 0.511 mev

Poron then interacts with a free electron and annihilate them both creating two futons 0.511 mev each

Most of the neutrons contaminating, a linear beam are produced in the

Target, flattening filter, collimators in the linac head

The photons produced during the orbital transition of electrons from a higher to lower energy are termed

Characteristic photos

The production of scattered radiation when X Ray strikes an object principally results from

Compton event

How many photon interaction processes occur in the energy range of concern and radiation therapy

Five

In the bremsstrahlung radiation, what happens to the incoming electron?

The incoming electron is deflected by the nucleus of the atom

Which type of interaction is sometimes described as a true absorption

Photoelectric

Mega volt imaging decreases soft tissue contrast because of the predominance of

Compton scattering

The interaction between an incident photon and an inner shell electron which transfers all of its energy of the proton to the electron is called

Photoelectric interaction

Which photo interaction with matter is most likely to occur with radiation therapy delivery via linear accelerators

The Compton effect because they produce high energy photons around 1 to 25 mev that primarily interact with loosely bound, outer shell electrons scattering the photon with reduce energy while causing ionization a process ideal for deep tissue penetration and dose delivery independent of atomic number

Which photo interaction with matter is most likely to occur with diagnostic imaging

Photoelectric interaction where a low energy, x-ray photo is completely absorbed by an inner shell electron creating the contrast that forms the image with a lower kvp

Which photo interaction with matters most likely to occur with radiation therapy via ortho voltage which operates at 200 to 500kv

Compton effect

What interaction is responsible for neutron contamination in radiation therapy

Photo nuclear reaction

Pair production is a common reaction occurring in the photon energy range of

How’s your threshold of 1.022 but most significant at 10 MEV

The force responsible for the interaction between particles with non-zero mass and having infinite range is

Gravity

The most common photo interaction that occurs in the energy range used in radiation therapy is

Compton scattering

To produce an electron pear in the vicinity of a nucleus, the interaction photo must have a minimum energy of

1.022 mev

To interact by the photoelectric effect photo must have an energy

Equal to or just greater than the binding energy of the electron

An incident Garay with an energy of 37 KEV strikes an orbit electron with a 40 KEV binding energy a scattered photon results with 37KEV of energy this describes

Coherent scattering

The photoelectric process is essentially an interaction between a photon and

Inner shell bounded electron

At energies above 10 MEV x-ray protons may interact directly with the atomic nucleus, causing the emission of nuclear fragments in a process called

Photo nuclear or photodisingration

Add photo energies of 100 KEV to 1MEV radiation is absorbed in soft tissue mainly by

Compton effect

The interaction of an x-ray in an orbital electron which result in a partial transfer of energy and ionization of the orbital electron is called

Compton scatter where an futon hits a loosely bound, outer shell electron transfer some of its energy to eject it, causing ionization and then scatters in a new direction with less energy

To undergo a Compton effect of the energy of the interacting photo must be

Very much Greater than the binding energy, but less than the energy needed for pair production

In a photoelectric interaction, the photo loses, how much of its energy

All of its energy

In the Compton interaction, the photo loses, how much of its energy

Half or part of its energy

Photoelectric effect involves a what electron

Inner shell electron

A Compton interaction involves a photon interaction with a

Outer shell electron or a free electron

During a photoelectric interaction, the incident photo is blank by the electron of the target item

Absorbed

Which interaction is most prevalent in radiation therapy?

Compton scattering

The Compton process involves an incoming photo what happens to that incoming photo?

It interacts with an outer shell electron and its energy is absorbed and scattered. It then produces a scatter electron and a recoil electron.

Which interaction is most likely an outer orbit interaction

Compton scattering

The blank interaction is the only interaction with the capability to produce a useful image on the CT detector or image receptor

Photoelectric