Erbium-159

Properties and data of the isotope ¹⁵⁹Er.

Content

General data

Name of the isotope:Erbium-159; Er-159Symbol:¹⁵⁹Er or 15968ErMass number A:159 (= number of nucleons)Atomic number Z:68 (= number of protons)Neutrons N:91Isotopic mass:158.930691(4) u (atomic weight of Erbium-159)Nuclide mass:158.8933909 u (calculated nuclear mass without electrons)Mass excess:-64.56092 MeVMass defect:1.389918532 u (per nucleus)Nuclear binding energy:1294.70077305 MeV (per nucleus)
8.14277216 MeV (average binding energy per nucleon)Separation energy:S_N = 7.329(25) MeV (first neutron)
S_P = 5.662(27) MeV (first proton)Half-life:36(1) minDecay constant λ:0.00032090147248146 s^-1Specific activity α:1.223110043952 × 10⁺¹⁸ Bq g^-1
33057028.214924 Ci g^-1Spin and parity:
(nuclear angular momentum)3/2-Magnetic dipole moment:μ(μ_N) = - 0.304(2)Quadrupole moment Q:+ 1.17(1) barn (100 fm²)Nuclear g-factor:g_l = -0.20266666666667Year of discovery:1962

Radioactive Decay

Half-life T_½ = 36(1) min (minutes) respectively 2.160 × 10³ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
EE/β⁺	¹⁵⁹Ho	100 %	2.768(5) MeV

Parent Nuclides

Direct parent isotope is: ¹⁵⁹Tm.

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 91) and isobaric (same nucleon number A = 159) with Erbium-159. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

OZ	Isotone N = 91	Isobar A = 159
52	¹⁴³Te
53	¹⁴⁴I
54	¹⁴⁵Xe
55	¹⁴⁶Cs
56	¹⁴⁷Ba
57	¹⁴⁸La
58	¹⁴⁹Ce
59	¹⁵⁰Pr	¹⁵⁹Pr
60	¹⁵¹Nd	¹⁵⁹Nd
61	¹⁵²Pm	¹⁵⁹Pm
62	¹⁵³Sm	¹⁵⁹Sm
63	¹⁵⁴Eu	¹⁵⁹Eu
64	¹⁵⁵Gd	¹⁵⁹Gd
65	¹⁵⁶Tb	¹⁵⁹Tb
66	¹⁵⁷Dy	¹⁵⁹Dy
67	¹⁵⁸Ho	¹⁵⁹Ho
68	¹⁵⁹Er	¹⁵⁹Er
69	¹⁶⁰Tm	¹⁵⁹Tm
70	¹⁶¹Yb	¹⁵⁹Yb
71	¹⁶²Lu	¹⁵⁹Lu
72	¹⁶³Hf	¹⁵⁹Hf
73	¹⁶⁴Ta	¹⁵⁹Ta
74	¹⁶⁵W	¹⁵⁹W
75	¹⁶⁶Re	¹⁵⁹Re
76	¹⁶⁷Os
77	¹⁶⁸Ir
78	¹⁶⁹Pt
79	¹⁷⁰Au
80	¹⁷¹Hg