92-U-237

Reaction 0.0253-eV Maxwellian
Average
g-factor Resonance
Integral
14-MeV Fiss. Spec.
Average
total 478.5 (b) 470.4 (b) 0.983 5.899 (b) 7.958 (b)
elastic 24.44 (b) 26.88 (b) 1.100 2.812 (b) 4.433 (b)
inelastic ( E-thr = 11.44 keV ) 498.4 (mb) 2.822 (b)
(n,2n) ( E-thr = 5.148 MeV ) 933.8 (mb) 33.74 (mb)
(n,3n) ( E-thr = 11.72 MeV ) 247.2 (mb) 34.99 (μb)
fission 1.702 (b) 1.674 (b) 0.983 45.87 (b) 1.399 (b) 594.5 (mb)
(n,fission) 1.702 (b) 1.674 (b) 0.983 45.67 (b) 431.1 (mb) 586.7 (mb)
(n,n,fiss) ( E-thr = 4.000 MeV ) 480.6 (mb) 7.715 (mb)
(n,2n,fiss) ( E-thr = 9.500 MeV ) 487.3 (mb) 90.82 (μb)
(n,4n) ( E-thr = 17.04 MeV ) 12.77 (nb)
(n,3nfiss) ( E-thr = 16.00 MeV ) 14.41 (nb)
capture 452.3 (b) 441.8 (b) 0.977 1.077 (kb) 823.1 (μb) 73.36 (mb)
 
νp 2.359 4.390
νd 3.284e-2 2.317e-2

These cross sections are calculated from JENDL-4.0 at 300K.
The background color of each cell noted a cross section means the order of the cross-section value.
The unit of cross section, (b), means barns, and SI prefixes are used as following.
(kb) → 103(b),   (mb) → 10−3(b),  (μb) → 10−6(b),  (nb) → 10−9(b).

Maxwellian Average :
σmacs(T) =
2
 
 
π
EU
 
EL
σ(E,T) ⋅ E ⋅ exp (
E
  
kBT
) dE
 
EU
 
EL
E ⋅ exp (
E
  
kBT
) dE
,
where T denotes the temperature, and kB the Boltzmann constant. The upper and lower limits of integration, EL and EU are set to 10−5 eV and 10 eV, respectively.
Resonance Integral :
σri(T) =
EU
 
EL
σ(E,T) ⋅
1
 
E
dE ,
with  EL = 0.5 eV  and  EU = 10 MeV.
U-235 Thermal Fission-Neutron Spectrum Average (Fiss. Spec. Average) :
σfacs(T) =
EU
 
EL
σ(E,T) ⋅
 
4
 
πa3b
⋅ exp (
ab E
     
4 a
) ⋅ sinh
 
bE
dE
 
EU
 
EL
 
4
 
πa3b
⋅ exp (
ab E
     
4 a
) ⋅ sinh
 
bE
dE
,
with  EL = 10−5 eV  and  EU = 20 MeV. The parameters a and b are 0.988 MeV and 2.249 MeV−1, respectively.
Westcott g-factor :
g(T) =
σmacs(T)
 
σ(0.0253 eV,T)
 .


νp, νd : numbers of prompt and delayed neutrons per fission.