X-Ray Production

Question 1

How are X-Ray Photons produced?

Answer 1

High-speed electrons from the cathode strike the anode target, transferring kinetic energy to the target atoms, resulting in photon emission.

Two types of interactions occur: Bremsstrahlung and characteristic interactions.

Question 2

What does the quantity (intensity) of the X-ray beam refer to?

Answer 2

The number of X-ray photons

mAs is the prime controller of quantity.

Question 3

What does the quality of the X-ray beam refer to?

Answer 3

The energy or penetrating ability of the X-ray beam

kVp is the prime controller of quality.

Question 4

What is the relationship between mAs and the number of electrons?

Answer 4

Direct relationship; increasing mAs increases the number of electrons.

2x mAs = 2x electrons, ½ mAs = ½ electrons.

Question 5

True or False: Increasing kVp affects the number of electrons.

Answer 5

False

kVp affects the speed of the electrons, not their number.

Question 6

What is the 15% rule in relation to kVp?

Answer 6

A 15% increase in kVp results in 2x the number of photons produced.

Question 7

What does increasing kVp do to the average and peak energy of X-ray photons?

Answer 7

Increases both average energy and peak energy (quality).

More photons are produced at every energy level.

Question 8

What is the average energy in an X-ray tube when the peak energy is set at 100 kVp?

Answer 8

30 to 40 kV

Question 9

What is the peak energy in an X-ray tube when the kVp is set at 70 kVp?

Answer 9

70 kV

Question 10

What happens to the majority of the energy from incident electrons in the target?

Answer 10

Over 99.8% is converted to heat.

Question 11

What are the two types of target interactions in X-ray production?

Answer 11

• Bremsstrahlung Interactions
• Characteristic Interactions

Question 12

What are Bremsstrahlung interactions?

Answer 12

Interactions that occur when an incident electron interacts with the force field of the nucleus, leading to photon emission due to energy loss.

This is the majority of photons created.

Question 13

What must happen for Bremsstrahlung interactions to occur?

Answer 13

The incident electron must have enough energy to approach the nucleus and interact with its force field.

Question 14

What are characteristic interactions?

Answer 14

Interactions that occur when an incident electron knocks an inner shell electron from its orbit, leading to photon emission as outer shell electrons fill the vacancy.

These photons are predictable and depend on the target material.

Question 15

What type of photon is emitted when an outer shell electron drops to fill a hole left by an inner shell electron?

Answer 15

Characteristic X-ray photon.

Question 16

What is the binding energy of a K-shell electron in a tungsten atom?

Answer 16

70 keV

Question 17

Fill in the blank: The electrons closest to the nucleus have ______ binding energy.

Answer 17

higher

Question 18

Fill in the blank: The electrons farthest from the nucleus have ______ binding energy.

Answer 18

lower