Index
255
Initiators (Po-Be neutron sources), xvii
Isotopes
electromagnetic separation of, 130, 237,
238, 240
gaseous diffusion, 137, 143
Ivy King test, 182
J
Joliot-Curie, Frédérick, 1, 7, 14
L
Lead (tamper), xvi
Little Boy
components, xiv
predetonation probability, 151, 152
simulation of, 88, 95, 96
tamper effect, 94
test units, xv
M
Marsden, Ernest, 5
Mass excess, 1–3, 13, 240, 241
Mass number, fission barrier vs., 30, 48
Mean free path (MFP)
neutron, 51, 59, 219
of fast neutrons in uranium, 59
transport, 59, 67, 73, 75, 100, 219
Meitner, Lise, 17, 188, 246
Momentum, conservation of in collisions,
193, 197
N
Neutron(s)
diffusion theory of, 65, 110, 111, 140,
169, 218, 219
discovery of, 6, 14, 16, 163, 247
emitted in fission, 21, 28, 82
energy spectrum of neutrons released in
fission, 27
escape probability from within sphere,
213
fast vs. slow, fission cross sections for,
30, 120
fission-spectrum average, 32, 193
flux, 52, 110, 129, 166, 168–171, 220,
221, 241
initiators, 145, 152, 166, 167
mean free path, 51, 52, 59, 67, 75, 219
number density, 55, 57, 59, 60, 62, 67,
83, 127, 150, 218–220, 223, 238
number of neutrons (N), 4, 19, 51, 54,
56–60, 83, 87, 88, 91, 93, 95, 103, 108,
121, 122, 129, 148, 157, 158, 161, 164,
172, 185, 186, 193, 219, 224, 230, 232,
238
secondary numbers, 151, 193
spherical geometry, 149
thermalization, 124, 127, 238
Nier, Alfred, 20
Nuclear explosion, graph of conditions
within, 157
Nuclear reactions, energy release in, 1, 3
Nuclear transmutation, artificial, 5, 6
Nuclear weapon
critical mass, U and Pu, 64
efficiency, 19, 52, 65, 81, 82, 93
tamper effect, vii
Nucleon number (A), 2–5, 9, 22, 236
O
Oppenheimer, Robert, 153, 166, 168, 170,
171
P
Paraffin, role in discovery of neutron, 17
Path length, reduced, 215, 216
Plutonium
bare critical mass, 63, 64
fission characteristics of, 172
nuclear properties, 129
production of, 35, 119, 127–129, 171,
187, 233, 245
spontaneous fission of, 148
Polonium (initiators), xvi
Predetonation
Fat Man, 152, 188
light-element impurities, 163
Little Boy, 152
yield model of, 156
Pressure, in exploding bomb core, 85
Q
Q-values, 1–5, 8, 9, 14, 15, 30, 31, 35, 196,
226, 228
R
Radioactivity
artificially induced, 6, 14, 15
neutron induced, 120
Radium decay, energy release in, 3
255
Initiators (Po-Be neutron sources), xvii
Isotopes
electromagnetic separation of, 130, 237,
238, 240
gaseous diffusion, 137, 143
Ivy King test, 182
J
Joliot-Curie, Frédérick, 1, 7, 14
L
Lead (tamper), xvi
Little Boy
components, xiv
predetonation probability, 151, 152
simulation of, 88, 95, 96
tamper effect, 94
test units, xv
M
Marsden, Ernest, 5
Mass excess, 1–3, 13, 240, 241
Mass number, fission barrier vs., 30, 48
Mean free path (MFP)
neutron, 51, 59, 219
of fast neutrons in uranium, 59
transport, 59, 67, 73, 75, 100, 219
Meitner, Lise, 17, 188, 246
Momentum, conservation of in collisions,
193, 197
N
Neutron(s)
diffusion theory of, 65, 110, 111, 140,
169, 218, 219
discovery of, 6, 14, 16, 163, 247
emitted in fission, 21, 28, 82
energy spectrum of neutrons released in
fission, 27
escape probability from within sphere,
213
fast vs. slow, fission cross sections for,
30, 120
fission-spectrum average, 32, 193
flux, 52, 110, 129, 166, 168–171, 220,
221, 241
initiators, 145, 152, 166, 167
mean free path, 51, 52, 59, 67, 75, 219
number density, 55, 57, 59, 60, 62, 67,
83, 127, 150, 218–220, 223, 238
number of neutrons (N), 4, 19, 51, 54,
56–60, 83, 87, 88, 91, 93, 95, 103, 108,
121, 122, 129, 148, 157, 158, 161, 164,
172, 185, 186, 193, 219, 224, 230, 232,
238
secondary numbers, 151, 193
spherical geometry, 149
thermalization, 124, 127, 238
Nier, Alfred, 20
Nuclear explosion, graph of conditions
within, 157
Nuclear reactions, energy release in, 1, 3
Nuclear transmutation, artificial, 5, 6
Nuclear weapon
critical mass, U and Pu, 64
efficiency, 19, 52, 65, 81, 82, 93
tamper effect, vii
Nucleon number (A), 2–5, 9, 22, 236
O
Oppenheimer, Robert, 153, 166, 168, 170,
171
P
Paraffin, role in discovery of neutron, 17
Path length, reduced, 215, 216
Plutonium
bare critical mass, 63, 64
fission characteristics of, 172
nuclear properties, 129
production of, 35, 119, 127–129, 171,
187, 233, 245
spontaneous fission of, 148
Polonium (initiators), xvi
Predetonation
Fat Man, 152, 188
light-element impurities, 163
Little Boy, 152
yield model of, 156
Pressure, in exploding bomb core, 85
Q
Q-values, 1–5, 8, 9, 14, 15, 30, 31, 35, 196,
226, 228
R
Radioactivity
artificially induced, 6, 14, 15
neutron induced, 120
Radium decay, energy release in, 3