Chapter 8

Question 1

X-ray production originate from

Answer 1

electron cloud

Question 2

Incoming electrons from the cathode =

Answer 2

incident electrons

Question 3

Travel from thermionic cloud around filament to target of anode at distance of

Answer 3

~2cm

Question 4

Range from nearly _ speed of

Answer 4

½ speed of light to the speed of light

Question 5

3 Target Interactions

Answer 5

Bremsstrahlung interactions
• Characteristic interactions
___

Question 6

Electron Interaction with Target Atoms produce

Answer 6

X-RAYS by 2 processes

Bremsstrahlung interactions
• Characteristic interactions

Question 7

German word for “braking or slowing”; also referred to as

Answer 7

Brems

Question 8

What interactions occur when an incident electron passes through orbital shells and approaches the nucleus of the Tungsten atom.

Answer 8

Brems

Question 9

What gets close to the nucleus because of the power of attraction.

Answer 9

Incident electron

Question 10

Electron cannot penetrate but the force field causes it to brake (slow down) this change in energy is emitted as an

Answer 10

x-ray photon.

Question 11

Bremsstrahlung Interaction- list 4 things about it

Answer 11

• Incident electron
• Passes by nucleus
• Changes direction
• Energy released as a photon

Question 12

Within diagnostic range, most photons are produced by

Answer 12

Brems target interactions.

Question 13

Photon energy dependent on

Answer 13

how close electron comes to nucleus and the rate of deceleration.

Question 14

Between 80-100 kVp, about 80-90% of the primary beam is produced by

Answer 14

Brems

Question 15

Most of the useful beam is of

Answer 15

Brems origin.

Question 16

What occur when an incident electron interacts with an inner-shell electron, the incident electron will continue but in another direction.

Answer 16

Characteristic Interactions

Question 17

An electron from another shell will immediately drop into the

Answer 17

vacant hole.

Question 18

This dropping of an electron from an outer higher energy into an inner low energy state results in the emission of an

Answer 18

x-ray photon.

Question 19

When outer-shell electrons fill inner-shell vacancies what occurs

Answer 19

a characteristic cascade occurs

Question 20

This produces several x-ray photons at different energies from each atom.

Answer 20

Characteristic Interactions

Question 21

Only incident electrons which drop into the __ will produce characteristic photons within diagnostic x-ray range. (characteristic peak)

Answer 21

K-shell

Question 22

Photons from other shells (L,M,N, etc.) have energies that are too low to be significant in diagnostic radiology. (this is what __ is for)

Answer 22

filtration

Question 23

kVp must be above __ for characteristic photons to contribute to a diagnostic image, this is due to the binding energy of Tungsten.

Answer 23

70

Question 24

Between 80-100 kVp, about 10-20% of the primary x-ray beam is produced by.

Answer 24

characteristic interactions

Question 25

Which spectrum has Continuous emissions wide variety of energy levels.

Answer 25

Brems

Question 26

What filters low x-ray energies out of the beam (area to far left of curve)

Answer 26

Filtration eliminates

Question 27

What spectrum discrete emissions of specific energy levels.

Answer 27

Characteristic Spectrum

Question 28

Factors that affect the emission spectrum.

Answer 28

mA kVp Filter

Question 29

For mA the larger the area under the curve, the

Answer 29

higher the x-ray quantity

Question 30

For kVp The farther the right, the

Answer 30

higher the quality (energy) of the x-ray beam and the greater amplitude.

Question 31

Adding filtration results in reduced quantity but

Answer 31

increased quality of the beam. (decreases amount of low energy x-rays)

Question 32

Target Material Higher Z#, increased what and shifts how

Answer 32

amplitude and shift to the right of the curve.

Question 33

More efficient generators create

Answer 33

higher amplitude

Question 34

Being human-made is the primary difference between

Answer 34

X-rays and gamma rays

Question 35

What is the products of nuclear radioactive decay

Answer 35

Gamma rays

Question 36

What is the distance that electrons that form the thermionic cloud around the filament arrive at the anode target travel

Answer 36

2 cm

Question 37

The electrons were accelerated from zero to

Answer 37

Half the speed of light in about 2 cm

Question 38

Incoming electrons are called

Answer 38

Incident electrons The ones that travel at the speed of light

Question 39

When incident electrons strike the target, they transfer their tremendous kinetic energy to the atoms of the target material and this interactions produces

Answer 39

Cray photons

Question 40

The greater the mass or speed of the incident electrons, the greater

Answer 40

The quality (energy) and quantity (number) of photons produced

Question 41

All target interactions occur within

Answer 41

.25-.5 mm of the surface of the target

Question 42

A these are two types of target interactions that can produce diagnostic range X-ray photons

Answer 42

Bremsstrahlung and characteristic