97-Bk-248

Reaction 0.0253-eV Maxwellian
Average
g-factor Resonance
Integral
14-MeV Fiss. Spec.
Average
total 2.871 (kb) 2.873 (kb) 1.001 5.964 (b) 8.121 (b)
elastic 10.12 (b) 11.44 (b) 1.131 2.872 (b) 4.519 (b)
inelastic ( E-thr = 50.20 keV ) 281.7 (mb) 1.913 (b)
(n,2n) ( E-thr = 5.504 MeV ) 323.2 (mb) 9.322 (mb)
(n,3n) ( E-thr = 12.08 MeV ) 10.32 (mb) 1.898 (μb)
fission 2.001 (kb) 2.001 (kb) 1.000 924.4 (b) 2.474 (b) 1.556 (b)
(n,fission) 2.001 (kb) 2.001 (kb) 1.000 924.4 (b) 2.016 (b) 1.553 (b)
(n,n,fiss) ( E-thr = 2.700 MeV ) 419.3 (mb) 2.539 (mb)
(n,2n,fiss) ( E-thr = 8.000 MeV ) 40.63 (mb) 5.638 (μb)
(n,4n) ( E-thr = 18.02 MeV ) 23.46e-12 (b)
(n,3nfiss) ( E-thr = 15.00 MeV ) 3.401e-12 (b)
capture 860.2 (b) 859.1 (b) 0.999 394.6 (b) 877.0 (μb) 122.4 (mb)
 
νp 3.664 6.576
νd 6.313e-3 4.331e-3

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.