Decay series and their energies

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    Alpha Decay Energy
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SUMMARY

The discussion focuses on the decay series of Uranium, specifically detailing the alpha and beta decay energies of isotopes within the Uranium series. Key isotopes include 238U, 234Th, and 226Ra, with total energies calculated for eight alpha decays summing to 43.355 MeV and six beta decays totaling 8.055 MeV. The conversation also raises questions about the average energy of beta particles emitted and the existence of shorter-lived gamma decays with significant branching fractions. The need for more specific data on gamma ray emissions and beta decay energy distribution is emphasized.

PREREQUISITES
  • Understanding of nuclear decay processes, specifically alpha and beta decay.
  • Familiarity with isotopes and their half-lives, particularly in the context of the Uranium series.
  • Knowledge of energy units used in nuclear physics, such as MeV (mega-electronvolts).
  • Experience with nuclear data tables and their application in decay energy calculations.
NEXT STEPS
  • Research the average energy of beta particles emitted in the Uranium decay series.
  • Investigate the characteristics of gamma decays in the Uranium series, focusing on branching fractions.
  • Explore nuclear data tables for comprehensive decay energy information.
  • Learn about the implications of antineutrino emissions in beta decay processes.
USEFUL FOR

Nuclear physicists, researchers in radioactive decay, and students studying nuclear chemistry will benefit from this discussion, particularly those interested in the specifics of Uranium decay series and their energy emissions.

snorkack
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The Wikipedia article
https://en.wikipedia.org/wiki/Decay_chain
has some numbers but fails to provide some sums and specifics I´d prefer.
The major natural ones:
Uranium series:
  1. 238U α 4.26975 4.468×109a
  2. 234Th β− 0.273088 24.10 d
  3. 234mPa β− 2.268205 1.159 min
  4. 234U α 4.8698 2.45×105a
  5. 230Th α 4.76975 7.54×104a
  6. 226Ra α 4.87062 1600 a
  7. 222Rn α 5.59031 3.8235 d
  8. 218Po α 6.11468 3.098 min
  9. 214Pb β− 1.019237 26.8 min
  10. 214Bi β− 3.269857 19.9 min
  11. 214Po α 7.83346 164.3 μs
  12. 210Pb β− 0.063487 22.20 a
  13. 210Bi β− 1.161234 5.012 d
  14. 210Po α 5.03647 138.376 d
No branches above 0,02% except the 234mPa γ decay that is also under 0,2 % and has little effect on the beta energy.
So, the 8 α decays are:
  1. 4.26975
  2. 4.8698
  3. 4.76975
  4. 4.87062
  5. 5.59031
  6. 6.11468
  7. 7.83346
  8. 5.03647
I get total 43,355 for these 8 alpha decays.
The 6 beta decays are:
  1. 0.273088
  2. 2.268205
  3. 1.019237
  4. 3.269857
  5. 0.063487
  6. 1.161234
Total thus 8,055 for these 6 beta decays.
But a large fraction of beta decay energies actually goes to antineutrinoes.
What is the actual total energy of beta particles emitted per uranium series, on average?
Also, beta decay of 234Th produces a long lived excited state - 0,16% of 1,159 min means a partial lifetime of about 12 h.
Are there any shorter lived gamma decays in uranium series with a bigger branching fraction? What is the maximum and total energy of gamma rays emitted by uranium series?
 
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