Thulium-173

Properties and data of the isotope ¹⁷³Tm.

Contents

General data

Name of the isotope:Thulium-173; Tm-173Symbol:¹⁷³Tm or 17369TmMass number A:173 (= number of nucleons)Atomic number Z:69 (= number of protons)Neutrons N:104Isotopic mass:172.939607(5) u (atomic weight of Thulium-173)Nuclide mass:172.9017584 u (calculated nuclear mass without electrons)Mass excess:-56.25572 MeVMass defect:1.501471472 u (per nucleus)Nuclear binding energy:1398.61166734 MeV (per nucleus)
8.0844605 MeV (average binding energy per nucleon)Separation energy:S_N = 6.953(7) MeV (first neutron)
S_P = 7.061(6) MeV (first proton)Half-life:8.24(8) hDecay constant λ:2.336661207389 × 10^-5 s^-1Specific activity α:8.181222635376 × 10⁺¹⁶ Bq g^-1
2211141.2528045 Ci g^-1Spin and parity:
(nuclear angular momentum)(1/2+)Year of discovery:1961

Radioactive Decay

Half-life T_½ = 8.24(8) h (hours) respectively 2.9664 × 10⁴ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
β^-	¹⁷³Yb	100 %	1.295(4) MeV

Parent Nuclides

Direct parent isotope is: ¹⁷³Er.

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 104) and isobaric (same nucleon number A = 173) with Thulium-173. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 104	Isobar A = 173
62	¹⁶⁶Sm
63	¹⁶⁷Eu
64	¹⁶⁸Gd
65	¹⁶⁹Tb
66	¹⁷⁰Dy	¹⁷³Dy
67	¹⁷¹Ho	¹⁷³Ho
68	¹⁷²Er	¹⁷³Er
69	¹⁷³Tm	¹⁷³Tm
70	¹⁷⁴Yb	¹⁷³Yb
71	¹⁷⁵Lu	¹⁷³Lu
72	¹⁷⁶Hf	¹⁷³Hf
73	¹⁷⁷Ta	¹⁷³Ta
74	¹⁷⁸W	¹⁷³W
75	¹⁷⁹Re	¹⁷³Re
76	¹⁸⁰Os	¹⁷³Os
77	¹⁸¹Ir	¹⁷³Ir
78	¹⁸²Pt	¹⁷³Pt
79	¹⁸³Au	¹⁷³Au
80	¹⁸⁴Hg	¹⁷³Hg
81	¹⁸⁵Tl
82	¹⁸⁶Pb
83	¹⁸⁷Bi
84	¹⁸⁸Po