Barium-136m

Properties and data of the isotope ^136mBa.

Contents

General data

Name of the isotope:Barium-136m; Ba-136mSymbol:^136mBa or 136m56BaMass number A:136 (= number of nucleons)Atomic number Z:56 (= number of protons)Neutrons N:80Isotopic mass:135.904576(2) u (atomic weight of Barium-136m)
Excitation energy: 2030.535(18) keVNuclide mass:135.8738576 u (calculated nuclear mass without electrons)Mass excess:-88.88688 MeVMass defect:1.226819072 u (per nucleus)Nuclear binding energy:1142.77460465 MeV (per nucleus)
8.40275445 MeV (average binding energy per nucleon)Half-life:308.4(19) msDecay constant λ:2.247558951232 s^-1Specific activity α:1.002601229283 × 10⁺²² Bq g^-1
270973305211.84 Ci g^-1Spin and parity:
(nuclear angular momentum)7-

Radioactive Decay

Half-life T_½ = 308.4(19) ms respectively 3.084 × 10^-1 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
Iso	¹³⁶Ba	100 %

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
¹³⁶Ba		stable	0+

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 80) and isobaric (same nucleon number A = 136) with Barium-136m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 80	Isobar A = 136
44	¹²⁴Ru
45	¹²⁵Rh
46	¹²⁶Pd
47	¹²⁷Ag
48	¹²⁸Cd
49	¹²⁹In	¹³⁶In
50	¹³⁰Sn	¹³⁶Sn
51	¹³¹Sb	¹³⁶Sb
52	¹³²Te	¹³⁶Te
53	¹³³I	¹³⁶I
54	¹³⁴Xe	¹³⁶Xe
55	¹³⁵Cs	¹³⁶Cs
56	¹³⁶Ba	¹³⁶Ba
57	¹³⁷La	¹³⁶La
58	¹³⁸Ce	¹³⁶Ce
59	¹³⁹Pr	¹³⁶Pr
60	¹⁴⁰Nd	¹³⁶Nd
61	¹⁴¹Pm	¹³⁶Pm
62	¹⁴²Sm	¹³⁶Sm
63	¹⁴³Eu	¹³⁶Eu
64	¹⁴⁴Gd	¹³⁶Gd
65	¹⁴⁵Tb	¹³⁶Tb
66	¹⁴⁶Dy
67	¹⁴⁷Ho
68	¹⁴⁸Er
69	¹⁴⁹Tm
70	¹⁵⁰Yb
71	¹⁵¹Lu