Talk:Alpha particle
 | This  level-4 vital article is rated C-class on Wikipedia's content assessment scale.It is of interest to the following WikiProjects: | ||||||||||
| |||||||||||
.jpg){kind=small}
|
|
|
|
This page has archives. Sections older than 90 days may be automatically archived by ClueBot III when more than 4 sections are present. | |
Symbol
[edit]The article currently states:
"If the ion gains electrons from its environment, the alpha particle can be written as a normal (electrically neutral) helium atom 4
2He."
This is unclear. How could the species still be an alpha particle if it has gained electrons to become an ordinary (neutral) helium atom?
—DIV (120.17.7.219 (talk) 12:48, 25 August 2017 (UTC))
- It is no longer an ion ... fixed. Vsmith (talk) 17:57, 25 August 2017 (UTC)
- Seems that this is all convention. Note that all our helium that comes out of the ground in natural gas originated as alpha particles, and got that name before it was known what they are. We could just as easily call the floating balloons alpha balloons, but that is not common. Once they slow down enough, and grab electrons off whatever is nearby, we call them helium. Gah4 (talk) 18:37, 24 November 2020 (UTC)
They then caused an electric spark inside the tube, which provided a shower of electrons that were taken up by the ions to form neutral atoms of a gas.
[edit]The article says: They then caused an electric spark inside the tube, which provided a shower of electrons that were taken up by the ions to form neutral atoms of a gas. This sounds a little strange to me. The alpha particles won't be a gas until they get electrons, which they likely will as soon as they hit the wall. As long as they don't go too far into the fall. Do they then stick? You can't get a spark through vacuum, but only through gas. It might be that heat is needed to get them off the wall, though. Gah4 (talk) 00:27, 2 October 2020 (UTC)
- I was about to say this, but it seems that I already did. Gah4 (talk) 18:32, 24 November 2020 (UTC)
- I guess the quoted sentence has since been removed. The spark bit in the article was still incorrect however.
- The Rutherford/Royds pair published two papers back to back. One was on the preparation and purification of the gas emitted by radium, lots of experimental details. The gist is that the carbon dioxide background was tough to get rid of. The second article was about the spectrum. With the gas in the tube, they created an electrical discharge and studied the emitted light to collect its spectral features. (I don't think He sticks to anything, so as soon as the alpha particle is neutralized its He gas). I added a ref to Pais "Inward Bound", who describes the experiment and result. Johnjbarton (talk) 02:22, 1 January 2024 (UTC)
Replacement of the Name section.
[edit]I rewrote the name section to give the origin of the name "alpha particle" and the connection to doubly ionized He atoms.
The previous section had no references and it has several claims about common usage (which probably cannot be verified unless some authority chose to say such). I suspect that when ever radioactivity is the source, the result is called "alpha particle" until the particle picks up two electrons and acts like a gas molecule, Helium. I doubt anyone calls the radiation product "doubly ionized Helium". On the other hand, if we start with Helium and ionize it, then yes we call it "doubly ionized Helium"; then it's not an alpha particle. The fact that these two products, from very different origins, have the same nucleons would not change the name used. I'll be on the look out for a reference to this effect. Johnjbarton (talk) 01:56, 1 January 2024 (UTC)
The smallest nuclei ?
[edit]An unsourced paragraph contains various claims about small or large nuclei, eg
- The smallest nuclei that have to date been found to be capable of alpha emission are beryllium-8 ...
Without a source I think this paragraph should be deleted as I don't know of any evidence relating nuclear diameter to alpha particle emission. Johnjbarton (talk) 17:49, 28 June 2024 (UTC)
- It is a little strange. Be8 seems like different physics, so probably shouldn't count. Mass instead of diameter might be a better claim. But I agree, remove is a good choice. Gah4 (talk) 19:54, 28 June 2024 (UTC)