Barium-140

Properties and data of the isotope ¹⁴⁰Ba.

Content

General data

Name of the isotope:Barium-140; Ba-140Symbol:¹⁴⁰Ba or 14056BaMass number A:140 (= number of nucleons)Atomic number Z:56 (= number of protons)Neutrons N:84Isotopic mass:139.910607(9) u (atomic weight of Barium-140)Nuclide mass:139.8798886 u (calculated nuclear mass without electrons)Mass excess:-83.26904 MeVMass defect:1.255447736 u (per nucleus)Nuclear binding energy:1169.4420334 MeV (per nucleus)
8.35315738 MeV (average binding energy per nucleon)Separation energy:S_N = 6.427(8) MeV (first neutron)
S_P = 9.857(9) MeV (first proton)Half-life:12.751(4) dDecay constant λ:6.291692268870 × 10^-7 s^-1Specific activity α:2.72586022233 × 10⁺¹⁵ Bq g^-1
73671.897901054 Ci g^-1Spin and parity:
(nuclear angular momentum)0+Charge radius:4.8684(59) femtometer fmYear of discovery:1939

Radioactive Decay

Half-life T_½ = 12.751(4) d respectively 1.1016864 × 10⁶ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
β^-	¹⁴⁰La	100 %	1.047(8) MeV

Parent Nuclides

Direct parent isotope is: ¹⁴⁰Cs.

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 84) and isobaric (same nucleon number A = 140) with Barium-140. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

OZ	Isotone N = 84	Isobar A = 140
47	¹³¹Ag
48	¹³²Cd
49	¹³³In
50	¹³⁴Sn
51	¹³⁵Sb	¹⁴⁰Sb
52	¹³⁶Te	¹⁴⁰Te
53	¹³⁷I	¹⁴⁰I
54	¹³⁸Xe	¹⁴⁰Xe
55	¹³⁹Cs	¹⁴⁰Cs
56	¹⁴⁰Ba	¹⁴⁰Ba
57	¹⁴¹La	¹⁴⁰La
58	¹⁴²Ce	¹⁴⁰Ce
59	¹⁴³Pr	¹⁴⁰Pr
60	¹⁴⁴Nd	¹⁴⁰Nd
61	¹⁴⁵Pm	¹⁴⁰Pm
62	¹⁴⁶Sm	¹⁴⁰Sm
63	¹⁴⁷Eu	¹⁴⁰Eu
64	¹⁴⁸Gd	¹⁴⁰Gd
65	¹⁴⁹Tb	¹⁴⁰Tb
66	¹⁵⁰Dy	¹⁴⁰Dy
67	¹⁵¹Ho	¹⁴⁰Ho
68	¹⁵²Er
69	¹⁵³Tm
70	¹⁵⁴Yb
71	¹⁵⁵Lu
72	¹⁵⁶Hf
73	¹⁵⁷Ta
74	¹⁵⁸W
75	¹⁵⁹Re