Erbium-148m

Properties and data of the isotope ¹⁴⁸Er.

Content

General data

Name of the isotope:Erbium-148m; Er-148mSymbol:¹⁴⁸Er or 14868ErMass number A:148 (= number of nucleons)Atomic number Z:68 (= number of protons)Neutrons N:80Isotopic mass:147.944735(11) u (atomic weight of Erbium-148m)
Excitation energy: 2913.2(4) keVNuclide mass:147.9074349 u (calculated nuclear mass without electrons)Mass excess:-51.47902 MeVMass defect:1.280560456 u (per nucleus)Nuclear binding energy:1192.8343814 MeV (per nucleus)
8.05969177 MeV (average binding energy per nucleon)Half-life:13(3) μsDecay constant λ:53319.013889227 s^-1Specific activity α:2.184317089481 × 10⁺²⁶ Bq g^-1
5.903559701302 × 10⁺¹⁵ Ci g^-1Spin and parity:
(nuclear angular momentum)(10+)

Radioactive Decay

Half-life T_½ = 13(3) μs respectively 1.3 × 10^-5 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
Iso	¹⁴⁸Er	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
¹⁴⁸Er		4.6(2) s	0+

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 80) and isobaric (same nucleon number A = 148) with Erbium-148m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

OZ	Isotone N = 80	Isobar A = 148
44	¹²⁴Ru
45	¹²⁵Rh
46	¹²⁶Pd
47	¹²⁷Ag
48	¹²⁸Cd
49	¹²⁹In
50	¹³⁰Sn
51	¹³¹Sb
52	¹³²Te
53	¹³³I
54	¹³⁴Xe	¹⁴⁸Xe
55	¹³⁵Cs	¹⁴⁸Cs
56	¹³⁶Ba	¹⁴⁸Ba
57	¹³⁷La	¹⁴⁸La
58	¹³⁸Ce	¹⁴⁸Ce
59	¹³⁹Pr	¹⁴⁸Pr
60	¹⁴⁰Nd	¹⁴⁸Nd
61	¹⁴¹Pm	¹⁴⁸Pm
62	¹⁴²Sm	¹⁴⁸Sm
63	¹⁴³Eu	¹⁴⁸Eu
64	¹⁴⁴Gd	¹⁴⁸Gd
65	¹⁴⁵Tb	¹⁴⁸Tb
66	¹⁴⁶Dy	¹⁴⁸Dy
67	¹⁴⁷Ho	¹⁴⁸Ho
68	¹⁴⁸Er	¹⁴⁸Er
69	¹⁴⁹Tm	¹⁴⁸Tm
70	¹⁵⁰Yb	¹⁴⁸Yb
71	¹⁵¹Lu