Lanthanum-132m

Properties and data of the isotope ¹³²La.

Content

General data

Name of the isotope:Lanthanum-132m; La-132mSymbol:¹³²La or 13257LaMass number A:132 (= number of nucleons)Atomic number Z:57 (= number of protons)Neutrons N:75Isotopic mass:131.91012(4) u (atomic weight of Lanthanum-132m)
Excitation energy: 188.20(11) keVNuclide mass:131.8788531 u (calculated nuclear mass without electrons)Mass excess:-83.72268 MeVMass defect:1.185775524 u (per nucleus)Nuclear binding energy:1104.54278595 MeV (per nucleus)
8.36774838 MeV (average binding energy per nucleon)Half-life:24.3(5) minDecay constant λ:0.00047540958886142 s^-1Specific activity α:2.185483595639 × 10⁺¹⁸ Bq g^-1
59067124.206478 Ci g^-1Spin and parity:
(nuclear angular momentum)6-

Radioactive Decay

Half-life T_½ = 24.3(5) min (minutes) respectively 1.458 × 10³ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
Iso	¹³²La	76 %
EE/β⁺	¹³²Ba	24 %

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
¹³²La		4.8(2) h	2-

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 75) and isobaric (same nucleon number A = 132) with Lanthanum-132m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

OZ	Isotone N = 75	Isobar A = 132
42	¹¹⁷Mo
43	¹¹⁸Tc
44	¹¹⁹Ru
45	¹²⁰Rh
46	¹²¹Pd
47	¹²²Ag	¹³²Ag
48	¹²³Cd	¹³²Cd
49	¹²⁴In	¹³²In
50	¹²⁵Sn	¹³²Sn
51	¹²⁶Sb	¹³²Sb
52	¹²⁷Te	¹³²Te
53	¹²⁸I	¹³²I
54	¹²⁹Xe	¹³²Xe
55	¹³⁰Cs	¹³²Cs
56	¹³¹Ba	¹³²Ba
57	¹³²La	¹³²La
58	¹³³Ce	¹³²Ce
59	¹³⁴Pr	¹³²Pr
60	¹³⁵Nd	¹³²Nd
61	¹³⁶Pm	¹³²Pm
62	¹³⁷Sm	¹³²Sm
63	¹³⁸Eu	¹³²Eu
64	¹³⁹Gd
65	¹⁴⁰Tb
66	¹⁴¹Dy
67	¹⁴²Ho
68	¹⁴³Er
69	¹⁴⁴Tm