20-Ca-42

MT Reaction 0.0253-eV Maxwellian
Average
g-factor Resonance
Integral
14-MeV Fiss. Spec.
Average
1 (n,total) 1.920 (b) 2.079 (b) 1.083 2.352 (b) 3.725 (b)
2 (n,elastic) 1.237 (b) 1.396 (b) 1.128 1.061 (b) 3.273 (b)
4 (n,inelastic) ( E-thr = 1.561 MeV ) 480.4 (mb) 438.2 (mb)
16 (n,2n) ( E-thr = 11.75 MeV ) 287.4 (mb) 42.97 (μb)
22 (n,na) ( E-thr = 6.399 MeV ) 211.1 (mb) 115.3 (μb)
28 (n,np) ( E-thr = 10.52 MeV ) 62.26 (mb) 11.25 (μb)
102 (n,γ) 683.1 (mb) 683.1 (mb) 1.000 375.1 (mb) 966.2 (nb) 2.563 (mb)
103 (n,p) ( E-thr = 2.801 MeV ) 207.2 (mb) 9.139 (mb)
107 (n,a) 0.000 (b) 0.000 (b) 33.80 (mb) 42.67 (mb) 2.675 (mb)

These cross sections are calculated from JENDL-3.2 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)
 .