Gold-195

Properties and data of the isotope ¹⁹⁵Au.

Content

General data

Name of the isotope:Gold-195; Au-195Symbol:¹⁹⁵Au or 19579AuMass number A:195 (= number of nucleons)Atomic number Z:79 (= number of protons)Neutrons N:116Isotopic mass:194.9650379(12) u (atomic weight of Gold-195)Nuclide mass:194.9217048 u (calculated nuclear mass without electrons)Mass excess:-32.56699 MeVMass defect:1.658269884 u (per nucleus)Nuclear binding energy:1544.66844733 MeV (per nucleus)
7.92137665 MeV (average binding energy per nucleon)Separation energy:S_N = 8.4264(23) MeV (first neutron)
S_P = 5.0959(10) MeV (first proton)Half-life:186.01(6) dDecay constant λ:4.312959954860 × 10^-8 s^-1Specific activity α:1.338827441826 × 10⁺¹⁴ Bq g^-1
3618.4525454776 Ci g^-1Spin and parity:
(nuclear angular momentum)3/2+Charge radius:5.4298(40) femtometer fmYear of discovery:1948

Radioactive Decay

Half-life T_½ = 186.01(6) d respectively 1.6071264 × 10⁷ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
EE	¹⁹⁵Pt	100 %	0.2268(12) MeV

Parent Nuclides

Direct parent isotope is: ¹⁹⁵Hg.

Nuclear Isomers

Nuclear isomers or excited states with the activation energy in keV related to the ground state.

Nuclear Isomer	Excitation Energy	Half-life	Spin
^195mAu	318.58(4) keV	30.5(2) s	11/2-

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 116) and isobaric (same nucleon number A = 195) with Gold-195. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

OZ	Isotone N = 116	Isobar A = 195
71	¹⁸⁷Lu
72	¹⁸⁸Hf
73	¹⁸⁹Ta
74	¹⁹⁰W	¹⁹⁵W
75	¹⁹¹Re	¹⁹⁵Re
76	¹⁹²Os	¹⁹⁵Os
77	¹⁹³Ir	¹⁹⁵Ir
78	¹⁹⁴Pt	¹⁹⁵Pt
79	¹⁹⁵Au	¹⁹⁵Au
80	¹⁹⁶Hg	¹⁹⁵Hg
81	¹⁹⁷Tl	¹⁹⁵Tl
82	¹⁹⁸Pb	¹⁹⁵Pb
83	¹⁹⁹Bi	¹⁹⁵Bi
84	²⁰⁰Po	¹⁹⁵Po
85	²⁰¹At	¹⁹⁵At
86	²⁰²Rn	¹⁹⁵Rn
87	²⁰³Fr
88	²⁰⁴Ra
89	²⁰⁵Ac