xray production Physics

The filament electrons interact with target atoms to produce X-rays in what following ways (2)

Characteristic interactions

Bremsstraulung (berms) interactions

Filament electrons penetrate the face of the target approx ______ interacting with the tungsten target atoms in its path

0.5mm

When a filament electron knocks out a ___ shell electron from the tungsten atom, it leads to a ______ x-ray photon

K

Characteristic

In characteristic interactions, outer shell electrons do what?

Drop to fill inner shell vacancies

The process of outer shell electrons filling inner shell vacencies

Characteristic cascades

The energy of the characteristic x-ray photon depends on what 3 things

Binding energy of inner shell electrons

Energy level of the filament electron

The shell of the electron that is dropping into the vacancy

The energy of the Brems photon depends on what 3 things

The original energy of the filament electrons

The strength of the attraction between the electron and the nucleus

The energy of the filament electron as it leaves the tungsten atom

The average energy of a brems photon is _____ of the kVp selected at they control console

1/3

With a tungsten target , most of the photons produced are _____

Brems

The use of a material, usually aluminum (AI) or aluminum equivalent, to absorb x-ray photons from the X-ray beam

Filtration

What is the primary controlling factor for beam quantity

MA

Total number of X-ray photons in a beam is referred to as

X-ray quantity

What is beam quantity affected by

Distance, filtration, mAs, kVp

If you would want to double the beam quantity what else do you have to double

MA

If kVp is doubled the intensity (quantity) increases by a factor of ____

4

A ___% increase in kVp is equivalent to doubling the mA

15

It is not recommended that kVp be used to control beam quantity because….? (3)

It affects scatter production

It affects penetrability of the beam

It is less predictable in how changing the kVp affects the image

Beam quantity varies inversely as what?

The inverse square law

As distance increases, the beam quantity reaching a specific area

Decreases

If the distance from the source is doubled, the quantity of radiation reaching a specific area is ____ the original

1/4

The inverse square law describes the relationship between what 2 things

Distance and beam intensity

Absorbs low energy photons that do not contribute to the image and would otherwise add to patient radiation dose

Filtration

Energy level or penetrating power of the X-ray beam

Beam quality

Refers to the X-ray beam as it is upon exiting the collimator d exposing the patient

Primary beam

Refers to the X-ray beam at remains after interaction with the patient and exits the patient to hit the image receptor

Remnant beam

Remnant radiation that passes through the patient without any interaction and did not interact with any anatomical structures

Transmitted radiation

Remnant radiation that did have an interaction with an anatomical structure

Scattered radiation

In the continuous emission spectrum, what does the x axis show

Energy level of photons

In the continuous emission spectrum what does the y axis show

Number of photons

Affects quality and quantity

KVp

If you add filtration in the path of the beam results in the X-ray emmison spectrum changing along the ____ and ____

X axis and y axis

Decrease quantity

Increase quality

What is the one thing that changes on the emission spectrum when changing target material

Discrete line

What is the primary controlling factor of beam quality

KVp

X-ray beams with high energy are what type of beam

High quality (hard)

X-ray beams with low energy are what type of beam

Low quality (soft)

Filtration removes the low energy electrons making the average beam energy ___

Higher making it a hard beam

What is the measurement for beam quality

Halve value layer HVL

What does HVL do

Reduced the intensity of the X-ray beam to one half of its original

What does the emission spectrum show

Graphic illustration of characteristic and bremsstrahlung radiation

What are characteristic photons on the emission spectrum

Discrete

Why is the characteristic production called discrete in the spectrum

Photon energies are limited to just a few exact values

For the tungsten target the discrete line on the X-ray emission spectrum is approx…

69 keV

With the X-ray emission spectrum the discrete line is……

The highest energy K characteristic bar

On the emission spectrum continuous illustrates……

Brems X-ray production

With a 75 kVp exposure, the energy of photons displayed on the continuous emission spectrum can range from….

Just above zero to 75 keV

With a 75 kVp exposure, the peak of the curve on the continuous emission spectrum is approx….

25 keV

The y-axis indicates change in….

Quantity

The x-axis indicates change in….

Quality

Changes in mA affect

Beam quantity

What axis is the number of X-rays

Y

Decreasing the mA results in fewer photons decreasing the levels along the ___ axis

Y

In increase in kVp increases what three things on the spectrum

Amplitude and continuous and discrete

How does the kVp shift on the spectrum when increased

Right side of curve to the right side along the x-axis

How does adding filtration affect the spectrum

Changing along the x and y axis