Barium-130

Properties and data of the isotope ¹³⁰Ba.

Contents

Barium-130 is part of the isotope mixture that makes up the earth´s barium deposits - albeit only at 0.1 percent. It is considered a primordial radioisotope that is very weakly radioactive due to the presence of the daughter nuclide Xenon-130 in rocks. The nuclide ¹³⁰Ba is also referred to as quasi-stable due to its very long half-life - i.e. radioactive decay events (double electron capture, 2EE) occur very rarely.

See also: List of individual Barium isotopes (and general data sources).

General data

Name of the isotope:Barium-130; Ba-130Symbol:¹³⁰Ba or 13056BaMass number A:130 (= number of nucleons)Atomic number Z:56 (= number of protons)Neutrons N:74Nucleon pairing (Z - N):even - evenNuclear ratio (N/Z ratio):1.3214285714286 (= neutron-proton ratio)Neutron excess (N-Z):18Isotopic mass:129.90632(2) u (atomic weight of Barium-130)Nuclide mass:129.8756016 u (calculated nuclear mass without electrons)Mass excess:-87.26236 MeVMass defect:1.173085576 u (per nucleus)Nuclear binding energy:1092.72217553 MeV (per nucleus)
8.4055552 MeV (average binding energy per nucleon)Separation energy:S_N = 10.267(11) MeV (first neutron)
S_P = 7.047(5) MeV (first proton)Half-life:1.6 × 10²¹ aDecay constant λ:1.373722056855 × 10^-29 s^-1Specific activity α:6.412982735493 × 10^-8 Bq g^-1
1.733238577160 × 10^-18 Ci g^-1Spin and parity:
(nuclear angular momentum)0+Charge radius:4.8283(47) femtometer fmYear of discovery:1936

Radioactive Decay

Half-life T_½ = 1.6 × 10²¹ a respectively 5.045760 × 10²⁸ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
2 EC	¹³⁰Xe

Parent Nuclides

Direct parent isotopes are: ¹³⁰La, ¹³⁰Cs.

Occurrence

Comparison of the natural Barium isotopes including isotopic abundance (mole fraction of the isotope mixture in percent):

	Atomic Mass m_a	Quantity	Half-life	Spin
Barium Isotopic mixture	137.327 u	100 %
Isotope ¹³⁰Ba	129.90632(2) u	0.11(1) %	1.6 × 10²¹ a	0+
Isotope ¹³²Ba	131.9050611(11) u	0.10(1) %	stable	0+
Isotope ¹³⁴Ba	133.904508(2) u	2.42(15) %	stable	0+
Isotope ¹³⁵Ba	134.905688(2) u	6.59(10) %	stable	3/2+
Isotope ¹³⁶Ba	135.904576(2) u	7.85(24) %	stable	0+
Isotope ¹³⁷Ba	136.905827(2) u	11.23(23) %	stable	3/2+
Isotope ¹³⁸Ba	137.905247(2) u	71.70(29) %	stable	0+

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
^130mBa	2475.12(18) keV	9.4(4) ms	8-

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 74) and isobaric (same nucleon number A = 130) with Barium-130. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 74	Isobar A = 130
41	¹¹⁵Nb
42	¹¹⁶Mo
43	¹¹⁷Tc
44	¹¹⁸Ru
45	¹¹⁹Rh
46	¹²⁰Pd
47	¹²¹Ag	¹³⁰Ag
48	¹²²Cd	¹³⁰Cd
49	¹²³In	¹³⁰In
50	¹²⁴Sn	¹³⁰Sn
51	¹²⁵Sb	¹³⁰Sb
52	¹²⁶Te	¹³⁰Te
53	¹²⁷I	¹³⁰I
54	¹²⁸Xe	¹³⁰Xe
55	¹²⁹Cs	¹³⁰Cs
56	¹³⁰Ba	¹³⁰Ba
57	¹³¹La	¹³⁰La
58	¹³²Ce	¹³⁰Ce
59	¹³³Pr	¹³⁰Pr
60	¹³⁴Nd	¹³⁰Nd
61	¹³⁵Pm	¹³⁰Pm
62	¹³⁶Sm	¹³⁰Sm
63	¹³⁷Eu	¹³⁰Eu
64	¹³⁸Gd
65	¹³⁹Tb
66	¹⁴⁰Dy
67	¹⁴¹Ho

External data and identifiers

Adopted Levels, Gammas:NuDat 130Ba

Literature and References

[1] - A. P. Meshik, C. M. Hohenberg, O. V. Pravdivtseva, Ya. S. Kapusta:
Weak decay of ¹³⁰Ba and ¹³²Ba: Geochemical measurements.
In: Physical Review C, (2001), DOI 10.1103/PhysRevC.64.035205.

[2] - Magali Pujol, Bernard Marty, Pete Burnard, Pascal Philippot:
Xenon in Archean barite: Weak decay of ¹³⁰Ba, mass-dependent isotopic fractionation and implication for barite formation.
In: Geochimica et Cosmochimica Acta, (2009), DOI 10.1016/j.gca.2009.08.002.