Europium-152

Properties and data of the isotope ¹⁵²Eu.

Contents

Eu-152 is a radioisotope of the chemical element Europium. The atomic nucleus of the nuclide is composed of 89 neutrons and 63 protons; this results in a mass number of 152.

General data

Name of the isotope:Europium-152; Eu-152Symbol:¹⁵²Eu or 15263EuMass number A:152 (= number of nucleons)Atomic number Z:63 (= number of protons)Neutrons N:89Isotopic mass:151.9217510(13) u (atomic weight of Europium-152)Nuclide mass:151.8871932 u (calculated nuclear mass without electrons)Mass excess:-72.88847 MeVMass defect:1.34240354 u (per nucleus)Nuclear binding energy:1250.44084309 MeV (per nucleus)
8.22658449 MeV (average binding energy per nucleon)Separation energy:S_N = 6.30672(10) MeV (first neutron)
S_P = 5.6010(5) MeV (first proton)Half-life:13.517(9) aDecay constant λ:1.626067389930 × 10^-9 s^-1Specific activity α:6485037662192.3 Bq g^-1
175.27128816736 Ci g^-1Spin and parity:
(nuclear angular momentum)3-Magnetic dipole moment:μ(μ_N) = - 1.9401(8)Quadrupole moment Q:+ 2.71(3) barn (100 fm²)Nuclear g-factor:g_l = -0.6467Charge radius:5.1064(66) femtometer fmYear of discovery:1938

Radioactive Decay

Half-life T_½ = 13.517(9) a respectively 4.26272112 × 10⁸ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
EC/β⁺	¹⁵²Sm	72.08(13) %	1.8743(18) MeV
β^-	¹⁵²Gd	27.92(13) %	1.8187(7) MeV

The diagram below shows a calculated spectrum with the most intense gamma emissions of the isotope europium-152:

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
^152m1Eu	45.5998(4) keV	9.3116(13) h	0-
^152m2Eu	65.2969(4) keV	0.94(8) μs	1-

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 89) and isobaric (same nucleon number A = 152) with Europium-152. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 89	Isobar A = 152
50	¹³⁹Sn
51	¹⁴⁰Sb
52	¹⁴¹Te
53	¹⁴²I
54	¹⁴³Xe
55	¹⁴⁴Cs
56	¹⁴⁵Ba	¹⁵²Ba
57	¹⁴⁶La	¹⁵²La
58	¹⁴⁷Ce	¹⁵²Ce
59	¹⁴⁸Pr	¹⁵²Pr
60	¹⁴⁹Nd	¹⁵²Nd
61	¹⁵⁰Pm	¹⁵²Pm
62	¹⁵¹Sm	¹⁵²Sm
63	¹⁵²Eu	¹⁵²Eu
64	¹⁵³Gd	¹⁵²Gd
65	¹⁵⁴Tb	¹⁵²Tb
66	¹⁵⁵Dy	¹⁵²Dy
67	¹⁵⁶Ho	¹⁵²Ho
68	¹⁵⁷Er	¹⁵²Er
69	¹⁵⁸Tm	¹⁵²Tm
70	¹⁵⁹Yb	¹⁵²Yb
71	¹⁶⁰Lu	¹⁵²Lu
72	¹⁶¹Hf
73	¹⁶²Ta
74	¹⁶³W
75	¹⁶⁴Re
76	¹⁶⁵Os
77	¹⁶⁶Ir
78	¹⁶⁷Pt