99-Es-255

MT Reaction 0.0253-eV Maxwellian
Average
g-factor Resonance
Integral
14-MeV Fiss. Spec.
Average
1 (n,total) 79.16 (b) 80.85 (b) 1.021 5.881 (b) 8.296 (b)
2 (n,elastic) 10.62 (b) 11.99 (b) 1.129 2.771 (b) 5.213 (b)
4 (n,inelastic) ( E-thr = 48.19 keV ) 4.936 (mb) 785.4 (mb)
16 (n,2n) ( E-thr = 6.007 MeV ) 111.0 (mb) 5.620 (mb)
17 (n,3n) ( E-thr = 11.12 MeV ) 224.3 (mb) 37.60 (μb)
18 (n,fission) 13.43 (b) 13.44 (b) 1.000 91.40 (b) 2.770 (b) 2.250 (b)
37 (n,4n) ( E-thr = 17.35 MeV ) 26.69 (nb)
102 (n,γ) 55.00 (b) 55.02 (b) 1.000 277.6 (b) 1.773 (nb) 38.31 (mb)

These cross sections are calculated from JENDL-3.3 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).

MT is a number that defines a reaction type. For the relation between MT and reaction type, please see here or refer to the manual of ENDF formats.

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)
 .