74-W-184

Reaction 0.0253-eV Maxwellian
Average
g-factor Resonance
Integral
14-MeV Fiss. Spec.
Average
total 9.070 (b) 10.02 (b) 1.105 5.539 (b) 6.943 (b)
elastic 7.372 (b) 8.323 (b) 1.129 3.034 (b) 4.514 (b)
inelastic ( E-thr = 105.0 keV ) 462.9 (mb) 2.376 (b)
(n,2n) ( E-thr = 7.452 MeV ) 2.042 (b) 7.490 (mb)
(n,3n) ( E-thr = 13.68 MeV ) 234.9 (μb) 10.15 (μb)
(n,na) 0.000 (b) 0.000 (b) 489.6 (nb) 46.39 (μb) 31.51 (nb)
(n,2na) ( E-thr = 5.763 MeV ) 5.352 (nb) 16.93e-12 (b)
(n,np) ( E-thr = 7.742 MeV ) 9.023 (μb) 12.26 (nb)
(n,nd) ( E-thr = 12.48 MeV ) 65.00e-24 (b) 8.356e-12 (b)
(n,nt) ( E-thr = 12.28 MeV ) 10.94e-24 (b) 1.525e-12 (b)
capture 1.698 (b) 1.699 (b) 1.001 16.60 (b) 708.6 (μb) 45.71 (mb)
(n,p) ( E-thr = 2.095 MeV ) 2.216 (mb) 623.4 (nb)
(n,d) ( E-thr = 5.506 MeV ) 151.3 (μb) 38.63 (nb)
(n,t) ( E-thr = 6.186 MeV ) 2.713 (μb) 1.750 (nb)
(n,He-3) ( E-thr = 6.544 MeV ) 20.30e-18 (b) 1.439e-15 (b)
(n,a) 38.28 (nb) 38.30 (nb) 1.001 7.149 (μb) 590.4 (μb) 678.6 (nb)

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)
 .