Samarium-132

Properties and data of the isotope ¹³²Sm.

Content

General data

Name of the isotope:Samarium-132; Sm-132Symbol:¹³²Sm or 13262SmMass number A:132 (= number of nucleons)Atomic number Z:62 (= number of protons)Neutrons N:70Isotopic mass:131.94087(32) u (atomic weight of Samarium-132)Nuclide mass:131.9068607 u (calculated nuclear mass without electrons)Mass excess:-55.07924 MeVMass defect:1.150826104 u (per nucleus)Nuclear binding energy:1071.98761092 MeV (per nucleus)
8.12111826 MeV (average binding energy per nucleon)Separation energy:S_N = 13.02(50) MeV (first neutron)
S_P = 2.71(36) MeV (first proton)Half-life:4.0(3) sDecay constant λ:0.17328679513999 s^-1Specific activity α:7.966087706106 × 10⁺²⁰ Bq g^-1
21529966773.262 Ci g^-1Spin and parity:
(nuclear angular momentum)0+Year of discovery:1989

Radioactive Decay

Half-life T_½ = 4.0(3) s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
EE/β⁺	¹³²Pm	100 %	6.55(33) MeV
EE, p	¹³¹Nd	?

Parent Nuclides

Direct parent isotope is: ¹³²Eu.

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 70) and isobaric (same nucleon number A = 132) with Samarium-132. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

OZ	Isotone N = 70	Isobar A = 132
39	¹⁰⁹Y
40	¹¹⁰Zr
41	¹¹¹Nb
42	¹¹²Mo
43	¹¹³Tc
44	¹¹⁴Ru
45	¹¹⁵Rh
46	¹¹⁶Pd
47	¹¹⁷Ag	¹³²Ag
48	¹¹⁸Cd	¹³²Cd
49	¹¹⁹In	¹³²In
50	¹²⁰Sn	¹³²Sn
51	¹²¹Sb	¹³²Sb
52	¹²²Te	¹³²Te
53	¹²³I	¹³²I
54	¹²⁴Xe	¹³²Xe
55	¹²⁵Cs	¹³²Cs
56	¹²⁶Ba	¹³²Ba
57	¹²⁷La	¹³²La
58	¹²⁸Ce	¹³²Ce
59	¹²⁹Pr	¹³²Pr
60	¹³⁰Nd	¹³²Nd
61	¹³¹Pm	¹³²Pm
62	¹³²Sm	¹³²Sm
63	¹³³Eu	¹³²Eu
64	¹³⁴Gd
65	¹³⁵Tb