2-He-8



Spin
     Level energy(keV)   Spin & Parity       
     ----------------------------------------
       ground state      0+                    
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)
     8.033934390 ± 0.000000095 (amu)  [mass excess = 31609.681 ± 0.089 (keV) ]
Beta-decay energy (calculated as M(A,Z)-M(A,Z+1), taken from Ame2012)
     10663.878 ± 0.100 (keV) 
Strong Gamma-rays from Decay of He- 8 (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 
  ----------------------------------------------------------
        980.             84.           B- 
  ----------------------------------------------------------
     *: relative, ~ approximate, ? calculated or estimatted 
     >: greater than or equal to, <: less than or equal to  
  [ Intensities; total intensity of the nuclide is 100(%). ]
Evaluated Data Libraries
     Links to the libraries. 

Parent Nuclides by Reactions in JENDL-4.0 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)
    -----------------------------------------------------------
     He-  8    U-235   Thermal   5.084850e-07   1.261040e-07 
     He-  8    U-235   Fast      4.477390e-07   1.110390e-07 
     He-  8    U-235   High      3.480500e-07   8.631640e-08 
     He-  8    U-238   Fast      3.984740e-07   9.882150e-08 
     He-  8    U-238   High      3.007150e-07   7.457730e-08 
     He-  8   Pu-239   Thermal   5.560250e-07   1.378940e-07 
     He-  8   Pu-239   Fast      5.000680e-07   1.240170e-07 
     He-  8   Pu-239   High      6.119570e-07   1.517650e-07 
     He-  8   Pu-241   Thermal   5.433360e-07   1.347470e-07 
     He-  8   Pu-241   Fast      5.258840e-07   1.304190e-07 
    -----------------------------------------------------------
    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)
    -----------------------------------------------------------
     He-  8    U-235   Thermal   5.084850e-07   1.261040e-07 
     He-  8    U-235   Fast      4.477390e-07   1.110390e-07 
     He-  8    U-235   High      3.480500e-07   8.631640e-08 
     He-  8    U-238   Fast      3.984740e-07   9.882150e-08 
     He-  8    U-238   High      3.007150e-07   7.457730e-08 
     He-  8   Pu-239   Thermal   5.560250e-07   1.378940e-07 
     He-  8   Pu-239   Fast      5.000680e-07   1.240170e-07 
     He-  8   Pu-239   High      6.119570e-07   1.517650e-07 
     He-  8   Pu-241   Thermal   5.433360e-07   1.347470e-07 
     He-  8   Pu-241   Fast      5.258840e-07   1.304190e-07 
    -----------------------------------------------------------
    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