Fission Flashcards
1
Q
Critical
A
k = 1.0000
2
Q
Sub-critical
A
k
3
Q
Super-critical
A
k >1
4
Q
Fissile
A
Thermal neutrons (235U, 233U, 239Pu)
5
Q
Fissionable
A
Fast neutrons (238U)
6
Q
Fertile
A
Fissile material can be bred from fertile nuclei
7
Q
Where does the energy go?
A
1) fission fragments, 2) fission neutrons, 3) prompt gammas, 4) electrons (B decay), 5) neutrinos (B decay), 6) gammas from B decay, 7) gammas from neutron capture
8
Q
Moderator
A
Slows down neutrons (water)
9
Q
Control rods
A
regulates number of neutrons per reaction that initiate reactions
10
Q
k
A
neutron multiplication factor
11
Q
Neutron gains
A
thermal fission, fast fission possible
12
Q
Losses
A
Absorption in fuel, absorption in other materials (moderator/fuel/cladding), escape from reactor
13
Q
n
A
thermal fission factor
14
Q
f
A
thermal utilisation factor
15
Q
p
A
resonance escape probability
