Uranium-radium series

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The uranium - radium series is the natural decay series of the uranium isotope 238 U.

It can be extended “backwards” to the artificial transuranium elements : The mother nuclide of uranium-238 is plutonium-242 , which is incubated in nuclear reactors . This can in turn have originated from other mother nuclides, which are not shown here (first extension in red ).
Your end nuclide is the stable lead isotope 206 Pb.

Radioactive decay series diagram.svg
Radioactive decay series: uranium-radium series (red)

In the case of the protactinium isotope 234 Pa, the metastable isomer 234m Pa is initially formed , which mainly decays via a β - process , but can also change to the ground state 234 Pa with a proportion of 0.16% due to γ decay .

4n + 2 row

Decay series of 238 U (the very unlikely series are not shown); Z shows the atomic number (number of protons), N the number of neutrons of the isotopes
In the gamma spectrum of uranium ore , various nuclides 226 Ra, 214 Pb, 214 Bi from the uranium-radium series can be recognized.
nuclide Decay HWZ E / MeV Decay product
242 Pu α 373300 a 4.984 238 U
238 U α 4.468 · 10 9 a 4,270 234 Th
234 Th β - 24.10 d 0.198 234m Pa
234m Pa β - 99.84%
IT 0.16% 		1.17 min 2.271
0.074 		234 U
234 Pa
234 Pa β - 6.7 h 2.197 234 U
234 U α 245500 a 4.859 230 th
230 th α 75380 a 4,770 226 Ra
226 Ra α 1602 a 4,871 222 para
222 para α 3.8235 d 5,590 218 Po
218 Po α 99.98%
β - 0.02% 		3.05 min 6.115
0.265 		214 Pb
218 at
218 at α 99.90%
β - 0.10% 		1.5 s 6,874
2,883 		214 Bi
218 Rn
218 para α 35 ms 7.263 214 Po
214 Pb β - 26.8 min 1.024 214 Bi
214 Bi β - 99.98%
α 0.02% 		19.9 min 3,272
5,617 		214 Po
210 Tl
214 Po α 164 µs 7,883 210 Pb
210 Tl β - 99.9930%
β - n 0.0070% 		1.30 min 5.484
0.299 		210 Pb
209 Pb *
210 Pb β - ≈ 100%
α 1.9 · 10 −6  % 		22.3 a 0.064
3.792 		210 Bi
206 Hg
210 bi β - 99.99987%
α 0.00013% 		5.013 d 1.161
5.036 		210 Po
206 Tl
206 ed β - 8.15 min 1.308 206 Tl
210 Po α 138.376 d 5.407 206 Pb
206 Tl β - 4.199 min 1.533 206 Pb
206 Pb . stable . .

* By neutron emission , a change takes place to neptunium decay series (4n + 1)