Gold-207

Properties and data of the isotope ²⁰⁷Au.

Content

General data

Name of the isotope:Gold-207; Au-207Symbol:²⁰⁷Au or 20779AuMass number A:207 (= number of nucleons)Atomic number Z:79 (= number of protons)Neutrons N:128Isotopic mass:206.98839(32) u (atomic weight of Gold-207)Nuclide mass:206.9450569 u (calculated nuclear mass without electrons)Mass excess:-10.81465 MeVMass defect:1.738896776 u (per nucleus)Nuclear binding energy:1619.77191346 MeV (per nucleus)
7.82498509 MeV (average binding energy per nucleon)Separation energy:S_N = 4.67(42) MeV (first neutron)
S_P = 8.47(42) MeV (first proton)Half-life:300 nsDecay constant λ:2310490.6018665 s^-1Specific activity α:6.75441740776 × 10⁺²⁷ Bq g^-1
1.825518218315 × 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^-	²⁰⁷Hg	?	5.68(30) MeV
β^-, n	²⁰⁶Hg	?	2.06(30) MeV

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 128) and isobaric (same nucleon number A = 207) with Gold-207. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

OZ	Isotone N = 128	Isobar A = 207
77	²⁰⁵Ir
78	²⁰⁶Pt	²⁰⁷Pt
79	²⁰⁷Au	²⁰⁷Au
80	²⁰⁸Hg	²⁰⁷Hg
81	²⁰⁹Tl	²⁰⁷Tl
82	²¹⁰Pb	²⁰⁷Pb
83	²¹¹Bi	²⁰⁷Bi
84	²¹²Po	²⁰⁷Po
85	²¹³At	²⁰⁷At
86	²¹⁴Rn	²⁰⁷Rn
87	²¹⁵Fr	²⁰⁷Fr
88	²¹⁶Ra	²⁰⁷Ra
89	²¹⁷Ac	²⁰⁷Ac
90	²¹⁸Th	²⁰⁷Th
91	²¹⁹Pa
92	²²⁰U
95	²²³Am