10. X ray production

Question 1

What are the two ways x rays are made?

Answer 1

1. Through charectorisitic radiation
2. Through Brehmmstralung radiation

Question 2

What shell is closest to the nucleus?

Answer 2

The K shell

Question 3

What type of radiation is florescence?

Answer 3

Charectoristic radiation

Question 4

How much of the beam intensity does charectoristic radiation contribute to? What is the range of kVp that it is created at?

Answer 4

Charectoristic radiation contributes to 0-10% of beam intensity. Range of kVp is 70-150 kVp

Question 5

How is a photon formed though charectorisitc radiation?

Answer 5

1. High speed e- travelling through the tube hit the tungsten atoms
2. An e- in the tungsten atom is knocked out of orbit
3. The subsequent e- move into the new spaces in the shell avalible since they are excited, and release energy in the form of an x ray photon as they move.

Question 6

How is charectorisitc radiation named?

Answer 6

Based off of which shell the e- move to

(k charectorisitc, ect.)

Question 7

What would release more energy; multi-level transitions, or single level transitions?

Answer 7

Multi level

higher transitions=higher energy=higher energy photons

Question 7

What removes low energy photons?

Answer 7

Filtration

Question 8

What is the k shells binding energy?

Answer 8

69.5 keV

Question 9

How does Bremsstrahlung radiation produce x ray photons?

Answer 9

1. As the e- travels in the tube, it is attracted to the tungsten atom, and slightly changes direction to go closer to the nucleus
2. As it changes direction, the e- slows down and releases energy as it turns
3. Energy lost is converted into x ray photons

Question 10

In bremmstahlung radiaton, how is higher energy photons created?

Answer 10

The sharper the turn of the e-, the more energy lost, which creates higher energy photons

Question 11

Why is it that with a higher energy e-, we can create more photons with Bremms radiaton?

Answer 11

After interacting with a tungsten atom, it can continue to interact with other tungsten atoms due to its high energy

Question 12

What are the different energy levels that charecterisitc radiation exists at?

Answer 12

1. Discrete spectrum
2. Line spectrum
3. Homogenous spectrum
4. Monoenergetic spectrum

Question 13

How could the same energy photon as the energy of the e- travelling in the tube be created?

Bremms

Answer 13

The e- would have to collide with the nucleus directly, without turning

Question 14

What are the different ways to describe Bremms energies?

Answer 14

1. Heterogenous
2. Continuous
3. Polyenergetic

Question 15

Define Intensity as a rate

Answer 15

Energy/area/time

Question 16

What affects the quality of charectorisitc radition intensity?

Answer 16

-Affected by changing the atomic #
-photons can only exist at the max energy of whatever the atomic # is.

Question 17

What affects the quantity of charectorisitc radiation intensity?

Answer 17

1. kVp
2. Ripple
3. mA
4. Z#

Question 18

How does increasing the kVp affect the quantity of charectoristic radiation?

Answer 18

As you increase kVp, you increase the amount of energy availbie to create photons since it has a higher chance to interact with k shell.

Question 19

How does decreasing ripple affect the quantity of charectorisitc radiation?

Answer 19

Decreasing ripple causes more e- to have the peak energy to make photons

Because we need a certian kVp to make char. radiation

Question 20

How does increasing the mA affect the quanitity of charectorisitc radiation?

Answer 20

Increasing mA allows **more ** e- to make photons

Question 21

How does increasing the atomic number affect charectorsisitc radiaton quanitity?

Answer 21

If the binding energy of the atom is close the the energy of the e- travelling through the tube, there is more chance that there will be an interaction.

The energy of the e- and the binding energy should not be too far off from eachother

Question 22

What affects the quality of Bremms radiation intensity?

Answer 22

1. kVp
2. Ripple
3. Z#

Question 23

What affects the quantity of Bremms radiation intensity?

Answer 23

1. kVp
2. Ripple
3. mA
4. Z#

Question 24

What is the limiting factor for the quality of Bremms radiation quality?

Answer 24

kVp

Question 25

How does increasing the kVp affect the quality of Bremms radiaiton?

Answer 25

As you increase kVp, it increases the peak energy of the photons

Question 26

How does increasing ripple affect the quality of bremms radiation?

Answer 26

Increasing the ripple decreases the avg energy of the photons and decreases the number of photons all together

(not good)

We want to decrease the ripple

Question 27

How does increasing the atomic # affect the quality of Bremms radiation?

Answer 27

As you increase the atomic number of the target, it increases the deceleration of electrons which increases energy of the photons

Question 28

How does decreasing the kVp affect the quantity of Bremms radiation?

Answer 28

Decreasing the kVp decreases the amount of energy avalible to create photons

(not good)

we want to increase the kVp to increase the chance of e- making more photons

Question 29

How does decreasing the ripple affect the quantity of Bremms radiation?

Answer 29

As you decrease the ripple, there is a higher average energy of e- that have the chance to interact with more atoms

Question 30

How does increasing the mA affect the quantity of Bremms radiation?

Answer 30

The higher mA, the more e- to make photons

Question 31

How does increasing atomic number affect the quantity of Bremms radiation?

Answer 31

Increasing the Z# decelerates more e- since higher atomic numbers are more positive

Question 32

What are the different shells starting from closest to the nucleus to the farthest?

Answer 32

1. K
2. L
3. M
4. N
5. O
6. P

Question 33

How do you find how much energy a charectorisitc photon will create?

Answer 33

Take the smaller biding E in the shell that the e- is moving from, and subtract is from the larger binding E that the e- is moving to.