Tellurium-129m

Properties and data of the isotope ^129mTe.

Contents

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

General data

Name of the isotope:Tellurium-129m; Te-129mSymbol:^129mTe or 129m52TeMass number A:129 (= number of nucleons)Atomic number Z:52 (= number of protons)Neutrons N:77Excitation energy:105.51(3) keVIsotopic mass:128.9065965(9) u (atomic weight of Tellurium-129m)Nuclide mass:128.8780721 u (calculated nuclear mass without electrons)Mass excess:-87.0048 MeVMass defect:1.167503696 u (per nucleus)Nuclear binding energy:1087.5226878 MeV (per nucleus)
8.43040843 MeV (average binding energy per nucleon)Half-life:33.6(1) dDecay constant λ:2.38765976548 × 10^-7 s^-1Specific activity α:1.123345580731 × 10⁺¹⁵ Bq g^-1
30360.69137113 Ci g^-1Spin and parity:
(nuclear angular momentum)11/2-Magnetic dipole moment:μ(μ_N) = - 1.091(7)Quadrupole moment Q:+0.40(3) barn (100 fm²)Nuclear g-factor:g_l = -0.19836363636364

Radioactive Decay

Half-life T_½ = 33.6(1) d respectively 2.903040 × 10⁶ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
β^-	¹²⁹I	36(7) %
Iso	¹²⁹Te	64(7) %

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
¹²⁹Te		69.6(3) min	3/2+

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 77) and isobaric (same nucleon number A = 129) with Tellurium-129m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 77	Isobar A = 129
43	¹²⁰Tc
44	¹²¹Ru
45	¹²²Rh
46	¹²³Pd	¹²⁹Pd
47	¹²⁴Ag	¹²⁹Ag
48	¹²⁵Cd	¹²⁹Cd
49	¹²⁶In	¹²⁹In
50	¹²⁷Sn	¹²⁹Sn
51	¹²⁸Sb	¹²⁹Sb
52	¹²⁹Te	¹²⁹Te
53	¹³⁰I	¹²⁹I
54	¹³¹Xe	¹²⁹Xe
55	¹³²Cs	¹²⁹Cs
56	¹³³Ba	¹²⁹Ba
57	¹³⁴La	¹²⁹La
58	¹³⁵Ce	¹²⁹Ce
59	¹³⁶Pr	¹²⁹Pr
60	¹³⁷Nd	¹²⁹Nd
61	¹³⁸Pm	¹²⁹Pm
62	¹³⁹Sm	¹²⁹Sm
63	¹⁴⁰Eu
64	¹⁴¹Gd
65	¹⁴²Tb
66	¹⁴³Dy
67	¹⁴⁴Ho
68	¹⁴⁵Er
69	¹⁴⁶Tm