97-Bk-245

Reaction 0.0253-eV Maxwellian
Average
g-factor Resonance
Integral
14-MeV Fiss. Spec.
Average
total 1.014 (kb) 1.017 (kb) 1.003 5.961 (b) 8.228 (b)
elastic 10.32 (b) 11.65 (b) 1.129 2.777 (b) 4.573 (b)
inelastic ( E-thr = 30.02 keV ) 359.0 (mb) 2.320 (b)
(n,2n) ( E-thr = 7.000 MeV ) 221.6 (mb) 1.346 (mb)
(n,3n) ( E-thr = 13.07 MeV ) 190.8 (μb) 115.0 (nb)
fission 2.902 (b) 2.907 (b) 1.002 5.294 (b) 2.599 (b) 1.088 (b)
(n,fission) 2.902 (b) 2.907 (b) 1.002 4.947 (b) 1.398 (b) 1.074 (b)
(n,n,fiss) ( E-thr = 2.300 MeV ) 1.181 (b) 13.50 (mb)
(n,2n,fiss) ( E-thr = 9.000 MeV ) 19.23 (mb) 3.169 (μb)
(n,3nfiss) ( E-thr = 15.50 MeV ) 7.657e-12 (b)
capture 1.000 (kb) 1.001 (kb) 1.000 1.077 (kb) 1.059 (mb) 243.5 (mb)
 
νp 3.575 6.235
νd 2.052e-3 1.418e-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.