Beta radiation and Alpha radiation

Click For Summary

Discussion Overview

The discussion revolves around the properties and behavior of beta and alpha radiation, particularly focusing on the interaction of beta particles with aluminum foil. Participants explore the mechanisms of absorption, ionization, and the safety implications of beta radiation in experimental settings.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant questions how aluminum foil can stop beta particles, wondering if they are reflected or can become outer-shell electrons of aluminum atoms.
  • Another participant clarifies that beta particles are ionizing, not ionized, and suggests that they are likely electrons, not protons.
  • There is a suggestion that when beta particles interact with aluminum, they may become outer-shell electrons, leading to a temporary negative charge on the aluminum.
  • Concerns are raised about the potential danger of ionizing radiation, with participants noting that both alpha and beta radiation can be harmful in sufficient quantities.
  • One participant proposes that many beta particles may be absorbed by aluminum, while some may bounce off, indicating a lack of consensus on the exact interactions.
  • Another participant discusses the energy loss of beta particles as they ionize atoms, leading to a decrease in their range within a medium.
  • There is mention of the effectiveness of aluminum as a shielding material against beta radiation, with one participant suggesting that only a few millimeters of aluminum would suffice for protection.

Areas of Agreement / Disagreement

Participants express various viewpoints on the interaction of beta particles with aluminum, with no clear consensus on the specifics of the absorption process or the implications for safety. Some agree on the general properties of beta radiation, while others question or refine earlier claims.

Contextual Notes

Participants note the dependence of beta particle behavior on the density of the medium and the energy loss mechanisms involved, but specific assumptions and definitions are not fully resolved.

Who May Find This Useful

This discussion may be of interest to those studying radiation physics, experimental safety in laboratories, or the interactions of particles with matter.

m_p_w
Messages
23
Reaction score
0
This might be a very stupid question :(, but I am confused.

So I did an experiment.
we had radioactive material which was emitting beta particles, and we were using geiger counter to measure pulses (ionized beta particles). We were supposed to measure the time it takes for the geiger counter to reach 1000 pulses and time difference by adding aluminum foils (thicker aluminum foil = longer time).

I am confused about two things,
-How it is possible that aluminum foil is able to stop beta particles? (what happens to beta particles in aluminum(are they just reflected from aluminum nucleus or can they become also outer-shell electron of aluminum atom, can beta particle get ionized in the aluminum foil (steal an electron from aluminum atom)?

-Are ionized beta particles dangerous? (ionized alpha particle are not because they become helium, what happens with beta particles?)
 
Last edited:
Science news on Phys.org
Beta particles aren't "ionized". They are "ionizing", perhaps that's what you mean. But alpha particles are ionized, they're helium atoms with a +2 charge - bare nuclei.

Your beta particles are probably electrons - "beta minus" (might be positrons, I doubt it). You seem to be thinking, incorrectly, they're protons - which would be ionized (+1). An electron hitting aluminum ... I suppose it becomes an outer-shell electron, making a +1 ion, which would soon get lost. Overall, aluminum will acquire a negative charge from beta radiation, soon lost to the environment.

Any such radiation, alpha or beta, will hurt you in sufficient quantities. For one thing they're pretty fast (carry energy and momentum), also they ionize atoms of your flesh. Both these things are disrupting. Obviously your lab experiment is designed to be safe - I hope - by involving a very small amount of radiation and/or appropriate shielding.
 
secur said:
Beta particles aren't "ionized". They are "ionizing", perhaps that's what you mean. But alpha particles are ionized, they're helium atoms with a +2 charge - bare nuclei.

Your beta particles are probably electrons - "beta minus" (might be positrons, I doubt it). You seem to be thinking, incorrectly, they're protons - which would be ionized (+1). An electron hitting aluminum ... I suppose it becomes an outer-shell electron, making a +1 ion, which would soon get lost. Overall, aluminum will acquire a negative charge from beta radiation, soon lost to the environment.

Any such radiation, alpha or beta, will hurt you in sufficient quantities. For one thing they're pretty fast (carry energy and momentum), also they ionize atoms of your flesh. Both these things are disrupting. Obviously your lab experiment is designed to be safe - I hope - by involving a very small amount of radiation and/or appropriate shielding.

So aluminum would acquire a beta particle (and loose it to the environment as free electron), and not just bounce it off to different directions?
 
I suppose many would get absorbed, giving the aluminum negative static-electricity charge, while some simply bounce off. But, sorry, others know those details much better than I do, so let them answer. I can say that such static electricity wouldn't be dangerous.
 
Sure, ##\beta## radiation (electrons) are partially absorbed by material like a aluminium foil.
 
Not sure what the mean free path of an electron in air at STP is but I assume it is short. Dusty room even shorter.
 
Every time a radioactive particle interacts with an atom, eg by ionising it, the energy needed to ionise the atom is lost from the particle and as a result the particle loses energy and slows down
. Eventually the particle will have lost so much energy that it becomes non ionising and in effect we can say that it has reached the end of its range. The denser the medium through which the particle travels the greater the number of collisions per unit length and the shorter the range.
 
secur said:
Obviously your lab experiment is designed to be safe - I hope - by involving a very small amount of radiation and/or appropriate shielding.
One thing I can read from the web, and is unsurprising to me, that free electrons would be stopped by a few millimeters of aluminum. Basically shielding wouldn't be hard at all, at worst it is probably a trip costing 2$ at least to the supermarket and back.
 

Similar threads

High School Can alpha radiation make other materials radioactive?
  • · Replies 8 ·
Replies
8
Views
4K
Can Geiger Counter Ticks be converted into particle/wave counts?
  • · Replies 12 ·
Replies
12
Views
2K
Graduate The effects of the alpha, beta and gamma radiation on humans
  • · Replies 1 ·
Replies
1
Views
8K
High School Alpha and beta radiation interaction
  • · Replies 4 ·
Replies
4
Views
2K
Graduate Relation of EM radiation equation to radioactive decay
  • · Replies 3 ·
Replies
3
Views
2K
Graduate How to detect alpha radiation without a counter?
  • · Replies 3 ·
Replies
3
Views
2K
Undergrad High energy beta particles (6 to 22 MeV)
  • · Replies 3 ·
Replies
3
Views
2K
Undergrad Alpha Particles: Is 'Radiation' a Misnomer?
  • · Replies 10 ·
Replies
10
Views
4K
High School If you are exposed to radiation, do you emit it?
  • · Replies 8 ·
Replies
8
Views
2K
Graduate Consequences to a medium after ionising radiation has passed through?
  • · Replies 1 ·
Replies
1
Views
1K