Lanthanum-151

Properties and data of the isotope ¹⁵¹La.

Content

General data

Name of the isotope:Lanthanum-151; La-151Symbol:¹⁵¹La or 15157LaMass number A:151 (= number of nucleons)Atomic number Z:57 (= number of protons)Neutrons N:94Isotopic mass:150.94277(47) u (atomic weight of Lanthanum-151)Nuclide mass:150.9115031 u (calculated nuclear mass without electrons)Mass excess:-53.3094 MeVMass defect:1.317758928 u (per nucleus)Nuclear binding energy:1227.48453488 MeV (per nucleus)
8.12903665 MeV (average binding energy per nucleon)Separation energy:S_N = 5.25(62) MeV (first neutron)
S_P = 10.70(53) MeV (first proton)Half-life:457 msDecay constant λ:1.5167334366738 s^-1Specific activity α:6.089321601750 × 10⁺²¹ Bq g^-1
164576259506.77 Ci g^-1Spin and parity:
(nuclear angular momentum)(1/2+)Year of discovery:1994

Radioactive Decay

Half-life T_½ = 457 ms respectively 4.57 × 10^-1 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
β^-	¹⁵¹Ce	100 %	7.91(44) MeV
β^-, n	¹⁵⁰Ce	?	3.47(44) MeV

Parent Nuclides

Direct parent isotope is: ¹⁵¹Ba.

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 94) and isobaric (same nucleon number A = 151) with Lanthanum-151. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

OZ	Isotone N = 94	Isobar A = 151
54	¹⁴⁸Xe
55	¹⁴⁹Cs	¹⁵¹Cs
56	¹⁵⁰Ba	¹⁵¹Ba
57	¹⁵¹La	¹⁵¹La
58	¹⁵²Ce	¹⁵¹Ce
59	¹⁵³Pr	¹⁵¹Pr
60	¹⁵⁴Nd	¹⁵¹Nd
61	¹⁵⁵Pm	¹⁵¹Pm
62	¹⁵⁶Sm	¹⁵¹Sm
63	¹⁵⁷Eu	¹⁵¹Eu
64	¹⁵⁸Gd	¹⁵¹Gd
65	¹⁵⁹Tb	¹⁵¹Tb
66	¹⁶⁰Dy	¹⁵¹Dy
67	¹⁶¹Ho	¹⁵¹Ho
68	¹⁶²Er	¹⁵¹Er
69	¹⁶³Tm	¹⁵¹Tm
70	¹⁶⁴Yb	¹⁵¹Yb
71	¹⁶⁵Lu	¹⁵¹Lu
72	¹⁶⁶Hf
73	¹⁶⁷Ta
74	¹⁶⁸W
75	¹⁶⁹Re
76	¹⁷⁰Os
77	¹⁷¹Ir
78	¹⁷²Pt
79	¹⁷³Au
80	¹⁷⁴Hg