97-Bk-250

Reaction 0.0253-eV Maxwellian
Average
g-factor Resonance
Integral
14-MeV Fiss. Spec.
Average
total 1.771 (kb) 1.779 (kb) 1.004 5.974 (b) 8.393 (b)
elastic 9.720 (b) 10.98 (b) 1.129 2.801 (b) 4.544 (b)
inelastic ( E-thr = 34.61 keV ) 337.0 (mb) 2.744 (b)
(n,2n) ( E-thr = 4.990 MeV ) 423.2 (mb) 36.12 (mb)
(n,3n) ( E-thr = 11.32 MeV ) 73.00 (mb) 10.19 (μb)
fission 980.6 (b) 982.7 (b) 1.002 623.5 (b) 2.334 (b) 1.013 (b)
(n,fission) 980.6 (b) 982.7 (b) 1.002 623.2 (b) 1.075 (b) 1.004 (b)
(n,n,fiss) ( E-thr = 2.300 MeV ) 864.8 (mb) 9.563 (mb)
(n,2n,fiss) ( E-thr = 7.000 MeV ) 395.0 (mb) 86.64 (μb)
(n,4n) ( E-thr = 16.82 MeV ) 4.051 (nb)
(n,3nfiss) ( E-thr = 13.50 MeV ) 25.56e-21 (b) 8.352 (nb)
capture 780.5 (b) 782.7 (b) 1.003 491.9 (b) 873.4 (μb) 53.40 (mb)

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)
 .