91-Pa-221
 basic

 element
91-protactinium-221

  • Atomic Mass: 221.0218637 +- 0.0000555 amu
  • Excess Mass: 20365.941 +- 51.669 keV
  • Binding Energy: 1692202.240 +- 51.670 keV
  • Beta Decay Energy: B- -4180.000 +- 116.000 keV #
"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.
  • Spin: 9/2-
  • Half life: 5.9 us
  • Mode of decay: Alpha to Ac-217
    • Decay energy: 9.250 MeV
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)