Lecture 5

Question 1

equation and definition

Answer 1

average distance a neutron travels from birth to absorption

Question 2

equation and definition

Answer 2

average time between the birth and absorption of a neutron

Question 3

in terms of A(0) and lamda for N(0) = 0

Answer 3

Question 4

for an infinite multiplying medium the neutron balance equation is

Answer 4

Question 5

equation and definition

Answer 5

average time between birth and the birth of a single neturon in the next generation

Question 6

define Γ

Answer 6

the ratio of the number of neutrons leaking from the system to the number of neutrons absorbed

Question 7

Γ =

Answer 7

Question 8

Answer 8

Question 9

equation and definition

Answer 9

average distance traveled between absorption OR leakage

Question 10

equation and definition

Answer 10

average lifetime between birth and loss (to absorption or leakage)

Question 11

for a finite multiplying medium (w/o external source) the neutron balance equation is

Answer 11

Question 12

for a finite multiplying medium with a constant external source

Answer 12

Question 13

Prompt inverse period eqn

Answer 13

Question 14

Delayed neutrons are emitted after ____ decay of ____

Answer 14

beta, fission products

Question 15

Delayed neutron fraction is ____ isotope dependent

Answer 15

strongly

Question 16

Delayed neutron fraction is ______ energy dependent

Answer 16

weakly

Question 17

The total delayed neutron precursoer decay constant is given by

Answer 17

Question 18

β is

Answer 18

the sum of the delayed fractions for each group

Question 19

equation and definition

Answer 19

average delayed neutron lifetime

Question 20

define

Answer 20

the number of radioactive precursors producing neutrons

Question 21

define

Answer 21

rate of delayed neutron production

Question 22

Precursors of type i produced per second equation

Answer 22

Question 23

Answer 23

Question 24

Neutron balance equation (in terms of k, β, and l) w/ delayed neutrons

Answer 24

Question 25

Precursor equation (in terms of k, β, and l)

Answer 25

Question 26

k with delayed neurtons

Answer 26

Question 27

l with delayed neutrons

Answer 27

Question 28

Neutron balance eqn in terms of reactivity and generation lifetime

Answer 28

Question 29

When the reactivity is not large, _____ can be approximated as 1

Answer 29

Λ

Question 30

The reactor period is determined by setting _____ equal to zero and finding a solution in the form ______ and ______.

Answer 30

source, n(t)=A*exp(ωt), and Ci(t) = Bi exp(ωt)

Question 31

The inhour equation is

Answer 31

Question 32

ω is _____ and is typically in units of _____

Answer 32

the inverse reactor period, inverse hours

Question 33

For positive reactivity, only _____ is positive. The remaining terms rapidly die away, yielding a solution in the form ______

Answer 33

ω₁, n(t) = A₁e^t/T

Question 34

For ρ >0, values of ω are

Answer 34

ω₁ > 0 > ω_1+i

Question 35

for ρ < 0, values of ω are

Answer 35

ω_i < 0

Question 36

For small reactivity ρ ≈ _____, T =

Answer 36

βω₁/λ, 1/ω₁

Question 37

For prompt critical, ρ ≈ _____, ω₁ = ______, T = _____

Answer 37

Question 38

Imediately following the reactivity change, the precursor concentration will remain essentially unchanged for as long as

Answer 38

λ_it<<1

Question 39

draw graph showing t vs power with and without thermal feedback after a prompt jump

Answer 39