90-Th-229

MT Reaction 0.0253-eV Maxwellian
Average
g-factor Resonance
Integral
14-MeV Fiss. Spec.
Average
1 (n,total) 104.2 (b) 108.7 (b) 1.043 6.189 (b) 7.604 (b)
2 (n,elastic) 9.960 (b) 11.18 (b) 1.122 3.141 (b) 5.127 (b)
4 (n,inelastic) ( E-thr = 100.4 eV ) 584.7 (mb) 1.738 (b)
16 (n,2n) ( E-thr = 5.272 MeV ) 302.5 (mb) 48.79 (mb)
17 (n,3n) ( E-thr = 12.42 MeV ) 110.2 (mb) 20.66 (μb)
18 (n,fission) 30.82 (b) 31.35 (b) 1.017 442.6 (b) 2.050 (b) 479.9 (mb)
37 (n,4n) ( E-thr = 17.90 MeV ) 41.69 (nb)
102 (n,γ) 63.38 (b) 66.13 (b) 1.043 1.236 (kb) 7.848 (μb) 204.6 (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)
 .