6.9 Appendix I: Glossary of Symbols
239
P O
initial pressure at center of bomb core (2.87)
P direct escape probability of a single neutron passing through a sample to escape; (2.7)
in Sect. 2.1
P e
reactor electrical power output (Sect. 3.3)
P escape
probability of neutron passing through layer of material (Sect. 2.1);
neutron-escape probability in predetonation analysis (Sects. 4.2, 4.3)
P n (cosθ )
Legendre polynomial of order n (Sect. 6.5)
P react
probability that incident particle will initiate reaction (Sect. 2.1)
P no predet
non-predetonation probability (Sects. 4.2, 4.3)
P t
reactor thermal power output (Sects. 3.3, 4.5)
p
momentum
Q
energy released or consumed in a reaction; fundamental definitions in
(1.2) and (1.10)
q
electric charge
R
radius of product nucleus in simulation of fission barrier (Sect. 1.11); ion
orbital radius in electromagnetic isotope separation (3.40) in Sect. 3.4;
rate of fissions in reactor (Sects. 3.3 and 5.3); carbon-to-uranium
number ratio in analysis of neutron reproduction in graphite (Sect. 4.1)
R α
rate of alpha-decay (Sect. 4.4)
R C
general critical radius (2.29)
R core
general core radius (Chap. 2)
R n
rate of neutron production from (α, n) reactions (Sect. 4.4)
R O
radius of initial nucleus in fission analysis (Sects. 1.7, 1.11, 6.5); rate
of neutron bombardment per square meter (Sect. 2.1); bare threshold
critical radius (Sect. 2.2)
R thresh
threshold critical radius for a tamped core (Sects. 2.3, 2.4)
R 1 , R 2
radii of product nuclei in fission analysis (Sect. 1.7); inner and outer
core radii in analysis of composite cores (Sect. 2.4)
r
general symbol for radius, often of a bomb core as a function of time
S
as a subscript, generally meaning surface area surface area of membrane
hole in gaseous diffusion analysis (Sect. 3.5); stopping power of
material against alpha-particles (4.28) in Sect. 4.4
SF
spontaneous fission
S max
maximum number of scatterings in predetonation analysis (Sect. 4.2)
T
absolute (Kelvin) temperature
t 1/2
half-life
t crit
time for bomb core to reach second criticality (2.94)
t fiss
time required to fission all material in bomb core (2.84). Also sometimes
written t fission
t fizzle
time by which the nuclear reaction in a core can be considered to have
begun if initiated at the moment of first criticality (Sect. 4.3)
t init
time at which chain reaction in core is initiated after first criticality
(Sect. 4.3)
t O
time to assemble bomb core following first criticality (Sect. 4.3)
U
energy density in bomb efficiency analysis (Sect. 2.5)
239
P O
initial pressure at center of bomb core (2.87)
P direct escape probability of a single neutron passing through a sample to escape; (2.7)
in Sect. 2.1
P e
reactor electrical power output (Sect. 3.3)
P escape
probability of neutron passing through layer of material (Sect. 2.1);
neutron-escape probability in predetonation analysis (Sects. 4.2, 4.3)
P n (cosθ )
Legendre polynomial of order n (Sect. 6.5)
P react
probability that incident particle will initiate reaction (Sect. 2.1)
P no predet
non-predetonation probability (Sects. 4.2, 4.3)
P t
reactor thermal power output (Sects. 3.3, 4.5)
p
momentum
Q
energy released or consumed in a reaction; fundamental definitions in
(1.2) and (1.10)
q
electric charge
R
radius of product nucleus in simulation of fission barrier (Sect. 1.11); ion
orbital radius in electromagnetic isotope separation (3.40) in Sect. 3.4;
rate of fissions in reactor (Sects. 3.3 and 5.3); carbon-to-uranium
number ratio in analysis of neutron reproduction in graphite (Sect. 4.1)
R α
rate of alpha-decay (Sect. 4.4)
R C
general critical radius (2.29)
R core
general core radius (Chap. 2)
R n
rate of neutron production from (α, n) reactions (Sect. 4.4)
R O
radius of initial nucleus in fission analysis (Sects. 1.7, 1.11, 6.5); rate
of neutron bombardment per square meter (Sect. 2.1); bare threshold
critical radius (Sect. 2.2)
R thresh
threshold critical radius for a tamped core (Sects. 2.3, 2.4)
R 1 , R 2
radii of product nuclei in fission analysis (Sect. 1.7); inner and outer
core radii in analysis of composite cores (Sect. 2.4)
r
general symbol for radius, often of a bomb core as a function of time
S
as a subscript, generally meaning surface area surface area of membrane
hole in gaseous diffusion analysis (Sect. 3.5); stopping power of
material against alpha-particles (4.28) in Sect. 4.4
SF
spontaneous fission
S max
maximum number of scatterings in predetonation analysis (Sect. 4.2)
T
absolute (Kelvin) temperature
t 1/2
half-life
t crit
time for bomb core to reach second criticality (2.94)
t fiss
time required to fission all material in bomb core (2.84). Also sometimes
written t fission
t fizzle
time by which the nuclear reaction in a core can be considered to have
begun if initiated at the moment of first criticality (Sect. 4.3)
t init
time at which chain reaction in core is initiated after first criticality
(Sect. 4.3)
t O
time to assemble bomb core following first criticality (Sect. 4.3)
U
energy density in bomb efficiency analysis (Sect. 2.5)