Polonium-227

Properties and data of the isotope ²²⁷Po.

Contents

See also: List of individual Polonium isotopes (and general data sources).

General data

Name of the isotope:Polonium-227; Po-227Symbol:²²⁷Po or 22784PoMass number A:227 (= number of nucleons)Atomic number Z:84 (= number of protons)Neutrons N:143Nucleon pairing (Z - N):even - oddNuclear ratio (N/Z ratio):1.702380952381 (= neutron-proton ratio)Neutron excess (N-Z):59Excitation energy:4.8(5) MeVIsotopic mass:227.04539(43) u (atomic weight of Polonium-227)Nuclide mass:226.9993147 u (calculated nuclear mass without electrons)Mass excess:42.28051 MeVMass defect:1.850995676 u (per nucleus)Nuclear binding energy:1724.19136622 MeV (per nucleus)
7.59555668 MeV (average binding energy per nucleon)Separation energy:S_N = 3.34(57) MeV (first neutron)Half-life:300 nsDecay constant λ:2310490.6018665 s^-1Specific activity α:6.129559409691 × 10⁺²⁷ Bq g^-1
1.65663767829 × 10⁺¹⁷ Ci g^-1Spin and parity:
(nuclear angular momentum)Year of discovery:2010

Radioactive Decay

Half-life T_½ = 300 ns respectively 3.0 × 10^-7 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
β^-	²²⁷At	?	4.8(5) MeV

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 143) and isobaric (same nucleon number A = 227) with Polonium-227. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 143	Isobar A = 227
84	²²⁷Po	²²⁷Po
85	²²⁸At	²²⁷At
86	²²⁹Rn	²²⁷Rn
87	²³⁰Fr	²²⁷Fr
88	²³¹Ra	²²⁷Ra
89	²³²Ac	²²⁷Ac
90	²³³Th	²²⁷Th
91	²³⁴Pa	²²⁷Pa
92	²³⁵U	²²⁷U
93	²³⁶Np	²²⁷Np
94	²³⁷Pu
95	²³⁸Am
96	²³⁹Cm
97	²⁴⁰Bk
98	²⁴¹Cf
99	²⁴²Es
100	²⁴³Fm
101	²⁴⁴Md