Level energy(keV)   Spin & Parity       
       ground state      1/2-                  
       1.03000E+02       7/2+                  
Mass (The Ame2012 atomic mass evaluation (II) by M.Wang, G.Audi, A.H.Wapstra, F.G.Kondev, M.MacCormick, X.Xu, and B.Pfeiffer Chinese Physics C36 p. 1603-2014, December 2012)
     80.917993023 ± 0.000001357 (amu)  [mass excess = -76389.007 ± 1.264 (keV) ]
Beta-decay energy (calculated as M(A,Z)-M(A,Z+1), taken from Ame2012)
     1586.644 ± 1.700 (keV) 
Strong Gamma-rays from Decay of Se- 81 (Compiled from ENSDF as of March 2011)
  [ Intensities before May 23th of 2013 were values when total intensity of the decay mode was 100(%) and a branching ratio of each decay mode was not multiplied. ]
   γ-ray energy(keV)  Intensity(%)  Decay mode 
        275.93            0.68         B- 
        290.04            0.56         B- 
        828.27            0.29         B- 
        103.01           12.79         IT 
        201.            3.E-03         B- 
        260.10            0.05         B- 
        275.93            0.05         B- 
     *: relative, ~ approximate, ? calculated or estimatted 
     >: greater than or equal to, <: less than or equal to  
  [ Intensities; total intensity of the nuclide is 100(%). ]
Decay data(Chart of the Nuclides 2014)
     Decay mode     Half-life 
       B-           18.45 M 12       
       B-           57.28 M 2        
       IT           57.28 M 2        
Evaluated Data Libraries
     Links to the libraries. 

Parent Nuclides by Reactions in JENDL-4.0
     Se- 80 (Z= 34, A= 80), MT=102 (n,γ)
     Se- 82 (Z= 34, A= 82), MT= 16 (n,2n)
     Br- 81 (Z= 35, A= 81), MT=103 (n,p)
     Kr- 83 (Z= 36, A= 83), MT=106 (n,3He)
     Kr- 84 (Z= 36, A= 84), MT=107 (n,α)
     Kr- 85 (Z= 36, A= 85), MT= 22 (n,nα)

Fission Yields for Fission Products in JENDL-4.0 Fission Yield Data

   - Neutron-induced Fission Yields (from main actinide nuclides) - Independent Fission Yield -
     Product  Nuclide  Energy   Fission Yield  Uncertainty(1σ)
     Se- 81    U-235   Thermal   1.057660e-05   2.432610e-06 
     Se- 81    U-235   Fast      5.162470e-06   3.303980e-06 
     Se- 81    U-235   High      1.369390e-05   8.764110e-06 
     Se- 81    U-238   Fast      3.474040e-07   2.223380e-07 
     Se- 81    U-238   High      5.318020e-06   3.403540e-06 
     Se- 81   Pu-239   Thermal   3.231520e-05   2.068180e-05 
     Se- 81   Pu-239   Fast      1.411290e-05   9.032260e-06 
     Se- 81   Pu-239   High      1.905680e-05   1.219630e-05 
     Se- 81   Pu-241   Thermal   4.416320e-06   2.826440e-06 
     Se- 81   Pu-241   Fast      2.773270e-06   1.774900e-06 
     Se- 81m   U-235   Thermal   6.894680e-05   1.585780e-05 
     Se- 81m   U-235   Fast      3.858720e-05   2.469580e-05 
     Se- 81m   U-235   High      1.641490e-04   1.050560e-04 
     Se- 81m   U-238   Fast      2.596700e-06   1.661880e-06 
     Se- 81m   U-238   High      6.374720e-05   4.079820e-05 
     Se- 81m  Pu-239   Thermal   2.106560e-04   1.348200e-04 
     Se- 81m  Pu-239   Fast      1.054880e-04   6.751210e-05 
     Se- 81m  Pu-239   High      2.284340e-04   1.461980e-04 
     Se- 81m  Pu-241   Thermal   2.878910e-05   1.842500e-05 
     Se- 81m  Pu-241   Fast      2.072910e-05   1.326660e-05 
    Thermal=0.0253eV, Fast=500keV(Fast reactor spectrum), High=14MeV
   - Neutron-induced Fission Yields (from main actinide nuclides) - Cumulative Fission Yield -
     Product  Nuclide  Energy   Fission Yield  Uncertainty(1σ)
     Se- 81    U-235   Thermal   1.900440e-03   1.588270e-04 
     Se- 81    U-235   Fast      2.145160e-03   5.413790e-04 
     Se- 81    U-235   High      3.293060e-03   5.584330e-04 
     Se- 81    U-238   Fast      7.954640e-04   2.837950e-04 
     Se- 81    U-238   High      3.149690e-03   5.622100e-04 
     Se- 81   Pu-239   Thermal   1.763150e-03   3.020550e-04 
     Se- 81   Pu-239   Fast      1.351640e-03   3.326550e-04 
     Se- 81   Pu-239   High      2.611870e-03   8.740030e-04 
     Se- 81   Pu-241   Thermal   5.821490e-04   2.025710e-04 
     Se- 81   Pu-241   Fast      8.652420e-04   2.203250e-04 
     Se- 81m   U-235   Thermal   2.310190e-04   5.313450e-05 
     Se- 81m   U-235   Fast      2.256230e-04   1.443990e-04 
     Se- 81m   U-235   High      4.414240e-04   2.825130e-04 
     Se- 81m   U-238   Fast      7.313430e-05   4.680580e-05 
     Se- 81m   U-238   High      3.379380e-04   2.162810e-04 
     Se- 81m  Pu-239   Thermal   3.459680e-04   1.910050e-04 
     Se- 81m  Pu-239   Fast      2.151480e-04   1.287690e-04 
     Se- 81m  Pu-239   High      4.388830e-04   2.563150e-04 
     Se- 81m  Pu-241   Thermal   7.764850e-05   4.969510e-05 
     Se- 81m  Pu-241   Fast      9.564820e-05   6.121490e-05 
    Thermal=0.0253eV, Fast=500keV(Fast reactor spectrum), High=14MeV
      → Neutron-induced and Spontaneous Fission Yields of all nuclides in JENDL-4.0 Fission Yield Data