Gold-173m

Properties and data of the isotope ¹⁷³Au.

Content

General data

Name of the isotope:Gold-173m; Au-173mSymbol:¹⁷³Au or 17379AuMass number A:173 (= number of nucleons)Atomic number Z:79 (= number of protons)Neutrons N:94Isotopic mass:172.986224(24) u (atomic weight of Gold-173m)
Excitation energy: 214(23) minNuclide mass:172.9428909 u (calculated nuclear mass without electrons)Mass excess:-12.83226 MeVMass defect:1.446455632 u (per nucleus)Nuclear binding energy:1347.36474247 MeV (per nucleus)
7.78823551 MeV (average binding energy per nucleon)Half-life:12.2(1) msDecay constant λ:56.815342668848 s^-1Specific activity α:1.989244166031 × 10⁺²³ Bq g^-1
5376335583868.4 Ci g^-1Spin and parity:
(nuclear angular momentum)(11/2-)

Radioactive Decay

Half-life T_½ = 12.2(1) ms respectively 1.22 × 10^-2 seconds s.

Decay mode	Daughter	Probability
α	¹⁶⁹Ir	92(13) %
p	¹⁷²Pt	?
EE/β⁺	¹⁷³Pt	?

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
¹⁷³Au		26.3(12) ms	(1/2+)

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 94) and isobaric (same nucleon number A = 173) with Gold-173m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

OZ	Isotone N = 94	Isobar A = 173
54	¹⁴⁸Xe
55	¹⁴⁹Cs
56	¹⁵⁰Ba
57	¹⁵¹La
58	¹⁵²Ce
59	¹⁵³Pr
60	¹⁵⁴Nd
61	¹⁵⁵Pm
62	¹⁵⁶Sm
63	¹⁵⁷Eu
64	¹⁵⁸Gd
65	¹⁵⁹Tb
66	¹⁶⁰Dy	¹⁷³Dy
67	¹⁶¹Ho	¹⁷³Ho
68	¹⁶²Er	¹⁷³Er
69	¹⁶³Tm	¹⁷³Tm
70	¹⁶⁴Yb	¹⁷³Yb
71	¹⁶⁵Lu	¹⁷³Lu
72	¹⁶⁶Hf	¹⁷³Hf
73	¹⁶⁷Ta	¹⁷³Ta
74	¹⁶⁸W	¹⁷³W
75	¹⁶⁹Re	¹⁷³Re
76	¹⁷⁰Os	¹⁷³Os
77	¹⁷¹Ir	¹⁷³Ir
78	¹⁷²Pt	¹⁷³Pt
79	¹⁷³Au	¹⁷³Au
80	¹⁷⁴Hg	¹⁷³Hg