Holmium-159m

Properties and data of the isotope ^159mHo.

Contents

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

General data

Name of the isotope:Holmium-159m; Ho-159mSymbol:^159mHo or 159m67HoMass number A:159 (= number of nucleons)Atomic number Z:67 (= number of protons)Neutrons N:92Isotopic mass:158.927719(3) u (atomic weight of Holmium-159m)
Excitation energy: 205.91(5) keVNuclide mass:158.8909673 u (calculated nuclear mass without electrons)Mass excess:-67.32932 MeVMass defect:1.393730416 u (per nucleus)Nuclear binding energy:1298.25152012 MeV (per nucleus)
8.1651039 MeV (average binding energy per nucleon)Half-life:8.30(8) sDecay constant λ:0.083511708501198 s^-1Specific activity α:3.183033367393 × 10⁺²⁰ Bq g^-1
8602792884.8476 Ci g^-1Spin and parity:
(nuclear angular momentum)1/2+

Radioactive Decay

Half-life T_½ = 8.30(8) s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
Iso	¹⁵⁹Ho	100 %

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
¹⁵⁹Ho		33.05(11) min	7/2-

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 92) and isobaric (same nucleon number A = 159) with Holmium-159m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 92	Isobar A = 159
53	¹⁴⁵I
54	¹⁴⁶Xe
55	¹⁴⁷Cs
56	¹⁴⁸Ba
57	¹⁴⁹La
58	¹⁵⁰Ce	¹⁵⁹Ce
59	¹⁵¹Pr	¹⁵⁹Pr
60	¹⁵²Nd	¹⁵⁹Nd
61	¹⁵³Pm	¹⁵⁹Pm
62	¹⁵⁴Sm	¹⁵⁹Sm
63	¹⁵⁵Eu	¹⁵⁹Eu
64	¹⁵⁶Gd	¹⁵⁹Gd
65	¹⁵⁷Tb	¹⁵⁹Tb
66	¹⁵⁸Dy	¹⁵⁹Dy
67	¹⁵⁹Ho	¹⁵⁹Ho
68	¹⁶⁰Er	¹⁵⁹Er
69	¹⁶¹Tm	¹⁵⁹Tm
70	¹⁶²Yb	¹⁵⁹Yb
71	¹⁶³Lu	¹⁵⁹Lu
72	¹⁶⁴Hf	¹⁵⁹Hf
73	¹⁶⁵Ta	¹⁵⁹Ta
74	¹⁶⁶W	¹⁵⁹W
75	¹⁶⁷Re	¹⁵⁹Re
76	¹⁶⁸Os
77	¹⁶⁹Ir
78	¹⁷⁰Pt
79	¹⁷¹Au
80	¹⁷²Hg