element
Information about Actinium-221:

WikipediaNeutron Cross SectionsX-Ray TransitionsX-Ray Attenuation

    Mass-Energy Data:

    Atomic Mass:221.015576±0.000054amu
    Excess Mass (Δ):14.508712±0.050495MeV
    Binding Energy:1699.624176±0.050496MeV
    β- Decay Energy:-2.417928±0.051397MeV
"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:

  • Half life: 52 ms ( 0.052 sec., λ = 13.3298 s-1)
  • Mode of decay:
    α
    to
    217
    87
    Fr
      (Q = 7.780 MeV)

  • Possible parent nuclides:
    α from
    225
    91
    Pa
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)