Are the daughter particles Ionized when the parent particle beta decays?

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SUMMARY

The discussion centers on the ionization of daughter particles resulting from beta decay and other radioactive decay processes. Daughter particles, such as alpha particles (He4 nuclei) and beta particles (electrons or positrons), are initially ionized but quickly neutralize due to interactions with surrounding matter. The ionization duration is extremely brief, typically less than 10 nanoseconds. The conversation also touches on the branching fractions of specific decay reactions, such as Re-187 to Os-187 and tritium decay into neutral helium, highlighting the complexities of energy distribution during these processes.

PREREQUISITES
  • Understanding of beta decay and its mechanisms
  • Familiarity with ionization processes in atomic physics
  • Knowledge of particle interactions and energy conservation
  • Basic principles of radioactive decay and photon emission
NEXT STEPS
  • Research the branching fractions of beta decay reactions, specifically for Re-187 and tritium.
  • Study the ionization energy of various elements, particularly osmium and helium.
  • Explore the principles of positron emission tomography (PET) and its relation to beta decay.
  • Investigate the experimental findings by Bosch et al. on bound-state beta decay.
USEFUL FOR

Physicists, nuclear engineers, and students studying particle physics and radioactive decay processes will benefit from this discussion.

rpthomps
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I was wondering if the resulting daughter element is ionized after the parent undergoes beta(or any other kind) of radioactive decay,
I was wondering if the resulting daughter element is ionized after the parent undergoes beta(or any other kind) of radioactive decay,
 
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Daughter particles (charges) such as alpha (He4 nucleus) or beta (electrons or positrons) are ions. However there are enough other things around to quickly neutralize.
 
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rpthomps said:
Summary:: I was wondering if the resulting daughter element is ionized after the parent undergoes beta(or any other kind) of radioactive decay,

I was wondering if the resulting daughter element is ionized after the parent undergoes beta(or any other kind) of radioactive decay,
Very briefly (less than an nanosecond (10-9 s), and probably on the order of 10-11 s). [I'll try to find an open source reference] Note that a beta particle is an electron and it will have a short range in the matter. It may collide with other electrons in the original atom, but it will interact with other electrons in neighboring atoms. The range in the material depends on the energy of the beta particle and type of material (electron density and binding energies of the atomic electrons). A positive ion will 'steal' an electron from a neighboring atom, which sets off a cascade of electrons jumping from other atoms until the original beta electron finds an ion and recombines.

When a positron (sometimes called a positive beta particle) is emitted, the atomic charge goes from Z to Z-1 and an atomic electron is emitted. The positron slows down through collisions until it combines with a negative electron and the pair annihilates into two photons of ~0.511 MeV. That is the basis of a PET scan. The atom that loses an electron then steals an electron from one of its neighbors and that starts a cascade of electron stealing until atom absorbs the free electron from the atom that emitted the positron.

In the case of the alpha particle, the atom number decreases by 2, i.e., Z -> Z-2, and so two electrons are lost. The alpha particle will slow down in the vicinity of the atom from which it came and become a helium atom, while the emitting atom will lose two electrons. Those free electrons will migrate to an available ion and recombine.
 
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It should be legal to produce a neutral atom by beta decay, but with a tiny branching fraction.
For the energy has to go somewhere. Consider the lowest energy of all beta decays... Re-187 to Os-187. 2600 eV minus the antineutrino share. The ionization energy of Os is 8,7 eV. What is the branching factor of the following reactions:
  1. Re-187 to any bound state of Os-187 and all the rest of energy to antineutrino?
  2. Re-187 to any bound state of Os-187 and the rest split between a continuum spectrum photon and continuum spectrum antineutrino?
Also, would the photon in this case be far UV or soft X-ray?
 
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Found an example. For a free neutron (decay energy 782 keV, total ionization energy 13,6 eV) the branching fraction for two body beta decay (only antineutrino emitted) is quoted as 4 per million. Not specified is the fraction for emitting antineutrino and photon, which also leaves a neutral atom.
Tritium has just 18 keV total decay energy and 24 eV ionization energy of He. What is the branching fraction for tritium decay into neutral He atom (with only antineutrino or also photon)?
 
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mathman said:
Daughter particles (charges) such as alpha (He4 nucleus) or beta (electrons or positrons) are ions. However there are enough other things around to quickly neutralize.
Thank you so much!
 
mathman said:
Daughter particles (charges) such as alpha (He4 nucleus) or beta (electrons or positrons) are ions. However there are enough other things around to quickly neutralize.
Thanks!
 
Astronuc said:
Very briefly (less than an nanosecond (10-9 s), and probably on the order of 10-11 s). [I'll try to find an open source reference] Note that a beta particle is an electron and it will have a short range in the matter. It may collide with other electrons in the original atom, but it will interact with other electrons in neighboring atoms. The range in the material depends on the energy of the beta particle and type of material (electron density and binding energies of the atomic electrons). A positive ion will 'steal' an electron from a neighboring atom, which sets off a cascade of electrons jumping from other atoms until the original beta electron finds an ion and recombines.

When a positron (sometimes called a positive beta particle) is emitted, the atomic charge goes from Z to Z-1 and an atomic electron is emitted. The positron slows down through collisions until it combines with a negative electron and the pair annihilates into two photons of ~0.511 MeV. That is the basis of a PET scan. The atom that loses an electron then steals an electron from one of its neighbors and that starts a cascade of electron stealing until atom absorbs the free electron from the atom that emitted the positron.

In the case of the alpha particle, the atom number decreases by 2, i.e., Z -> Z-2, and so two electrons are lost. The alpha particle will slow down in the vicinity of the atom from which it came and become a helium atom, while the emitting atom will lose two electrons. Those free electrons will migrate to an available ion and recombine.
Wow! Thanks for the reply!
 
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mathman said:
Daughter particles (charges) such as alpha (He4 nucleus) or beta (electrons or positrons) are ions. However there are enough other things around to quickly neutralize.
Thank you!
 

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