element
Information about Thorium-231:

WikipediaNeutron Cross SectionsX-Ray TransitionsX-Ray Attenuation

    Mass-Energy Data:

    Atomic Mass:231.036297±0.000002amu
    Excess Mass (Δ):33.810488±0.002023MeV
    Binding Energy:1760.253274±0.002047MeV
    β- Decay Energy:0.389515±0.001685MeV
"The 1995 update to the atomic mass evaluation" by G.Audi and A.H.Wapstra, Nuclear Physics A595 vol. 4 p.409-480, December 25, 1995.
Radioactive Decay Data:

  • Spin: 5/2+
  • Half life: 25.52 h ( 91872 sec., λ = 7.54471×10-06 s-1)
  • Mode of decay:
    β-
    to
    231
    91
    Pa
      (Q = 0.389 MeV)
  • Mode of decay: α to
    227
    88
    Ra
      (Q = 4.213 MeV)   Branch ratio: ~1.0E-8 %

  • Possible parent nuclides:
    β- from
    231
    89
    Ac
    α from
    235
    92
    U
R.R.Kinsey, et al.,The NUDAT/PCNUDAT Program for Nuclear Data,paper submitted to the 9 th International Symposium of Capture-Gamma_raySpectroscopy and Related Topics, Budapest, Hungary, Octover 1996.Data extracted from NUDAT database (Jan. 14/1999)