99-Es-254m

MT Reaction 0.0253-eV Maxwellian
Average
g-factor Resonance
Integral
14-MeV Fiss. Spec.
Average
1 (n,total) 2.261 (kb) 2.264 (kb) 1.002 6.001 (b) 8.422 (b)
2 (n,elastic) 9.419 (b) 10.64 (b) 1.129 2.795 (b) 4.437 (b)
4 (n,inelastic) 300.1 (μb) 300.2 (μb) 1.000 6.850 (b) 343.0 (mb) 1.997 (b)
16 (n,2n) ( E-thr = 5.029 MeV ) 403.5 (mb) 27.00 (mb)
17 (n,3n) ( E-thr = 11.41 MeV ) 76.46 (mb) 11.09 (μb)
18 (n,fission) 2.001 (kb) 2.001 (kb) 1.000 1.426 (kb) 2.377 (b) 1.913 (b)
19 (n,f) 2.001 (kb) 2.001 (kb) 1.000 1.426 (kb) 1.340 (b) 1.905 (b)
20 (n,nf) ( E-thr = 2.300 MeV ) 729.1 (mb) 8.095 (mb)
21 (n,2nf) ( E-thr = 7.000 MeV ) 309.1 (mb) 67.23 (μb)
37 (n,4n) ( E-thr = 16.72 MeV ) 12.20 (nb)
38 (n,3nf) ( E-thr = 14.00 MeV ) 0.000 (b) 3.680 (nb)
102 (n,γ) 250.1 (b) 250.5 (b) 1.001 178.3 (b) 822.2 (μb) 44.04 (mb)
 
456 νp 4.077 7.493
455 νd 5.999e-3 4.107e-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).

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)
 .


νp, νd : numbers of prompt and delayed neutrons per fission.