Thulium-146

Properties and data of the isotope ¹⁴⁶Tm.

Contents

General data

Name of the isotope:Thulium-146; Tm-146Symbol:¹⁴⁶Tm or 14669TmMass number A:146 (= number of nucleons)Atomic number Z:69 (= number of protons)Neutrons N:77Isotopic mass:145.96666(21) u (atomic weight of Thulium-146)Nuclide mass:145.9288114 u (calculated nuclear mass without electrons)Mass excess:-31.05601 MeVMass defect:1.24046574 u (per nucleus)Nuclear binding energy:1155.48639402 MeV (per nucleus)
7.91429037 MeV (average binding energy per nucleon)Separation energy:S_N = 11.54(28) MeV (first neutron)Half-life:68(3) msDecay constant λ:10.193340890587 s^-1Specific activity α:4.233498943204 × 10⁺²² Bq g^-1
1144188903568.9 Ci g^-1Spin and parity:
(nuclear angular momentum)(5-)Year of discovery:1993

Radioactive Decay

Half-life T_½ = 68(3) ms respectively 6.8 × 10^-2 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
p	¹⁴⁵Er	?	13.27(20) MeV
EE/β⁺	¹⁴⁶Er	?

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 77) and isobaric (same nucleon number A = 146) with Thulium-146. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

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