Lanthanum-144

Properties and data of the isotope ¹⁴⁴La.

Contents

General data

Name of the isotope:Lanthanum-144; La-144Symbol:¹⁴⁴La or 14457LaMass number A:144 (= number of nucleons)Atomic number Z:57 (= number of protons)Neutrons N:87Isotopic mass:143.919646(14) u (atomic weight of Lanthanum-144)Nuclide mass:143.8883791 u (calculated nuclear mass without electrons)Mass excess:-74.84927 MeVMass defect:1.280228516 u (per nucleus)Nuclear binding energy:1192.52518128 MeV (per nucleus)
8.28142487 MeV (average binding energy per nucleon)Separation energy:S_N = 4.750(15) MeV (first neutron)
S_P = 8.201(15) MeV (first proton)Half-life:40.8(4) sDecay constant λ:0.016988901484312 s^-1Specific activity α:7.154514531057 × 10⁺¹⁹ Bq g^-1
1933652575.9614 Ci g^-1Spin and parity:
(nuclear angular momentum)(3-)Year of discovery:1967

Radioactive Decay

Half-life T_½ = 40.8(4) s respectively 4.08 × 10¹ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
β^-	¹⁴⁴Ce	100 %	5.582(13) MeV

Parent Nuclides

Direct parent isotope is: ¹⁴⁴Ba.

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 87) and isobaric (same nucleon number A = 144) with Lanthanum-144. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 87	Isobar A = 144
49	¹³⁶In
50	¹³⁷Sn
51	¹³⁸Sb
52	¹³⁹Te
53	¹⁴⁰I	¹⁴⁴I
54	¹⁴¹Xe	¹⁴⁴Xe
55	¹⁴²Cs	¹⁴⁴Cs
56	¹⁴³Ba	¹⁴⁴Ba
57	¹⁴⁴La	¹⁴⁴La
58	¹⁴⁵Ce	¹⁴⁴Ce
59	¹⁴⁶Pr	¹⁴⁴Pr
60	¹⁴⁷Nd	¹⁴⁴Nd
61	¹⁴⁸Pm	¹⁴⁴Pm
62	¹⁴⁹Sm	¹⁴⁴Sm
63	¹⁵⁰Eu	¹⁴⁴Eu
64	¹⁵¹Gd	¹⁴⁴Gd
65	¹⁵²Tb	¹⁴⁴Tb
66	¹⁵³Dy	¹⁴⁴Dy
67	¹⁵⁴Ho	¹⁴⁴Ho
68	¹⁵⁵Er	¹⁴⁴Er
69	¹⁵⁶Tm	¹⁴⁴Tm
70	¹⁵⁷Yb
71	¹⁵⁸Lu
72	¹⁵⁹Hf
73	¹⁶⁰Ta
74	¹⁶¹W
75	¹⁶²Re
76	¹⁶³Os
77	¹⁶⁴Ir