Talk:Wu experiment

weak boson coupling
in the text: "due to the W and Z gauge bosons of the weak interaction coupling only to left-handed matter particles and the right-handed antimatter particles". Z bosons do couple to left and right handed particles (with different strength), the charged W couples only to left-handed particles.

217.224.249.27 (talk) 04:52, 19 January 2013 (UTC)Hallo

But why?
Nice article, but I don't entirely get it. There must be some kind of fairly simple analysis that can be given: e.g. 'if the P operator is applied to the nucleus, then one would get ..blah', etc. I don't really understand why one can look at the asymetry and deduce parity violation. There are some kind of missing steps here. User:Linas (talk) 23:19, 30 November 2013 (UTC)
 * One explanation is to put the Co60 in an electromagnet. If you change from left handed to right handed, you change the winging of the electromagnet, which changes the direction of the magnetic field. That exchanged up and down, such that beta goes the other way. Gah4 (talk) 06:30, 8 October 2020 (UTC)
 * One explanation is to put the Co60 in an electromagnet. If you change from left handed to right handed, you change the winging of the electromagnet, which changes the direction of the magnetic field. That exchanged up and down, such that beta goes the other way. Gah4 (talk) 06:30, 8 October 2020 (UTC)

The First problem
The first paragraph is unclear or contains a simple error: "it would be possible to distinguish between a mirrored version of the world and the mirror image of the current world." There are no circumstances under which one can distinguish between one thing described in two different ways, unless we are talking about distinguishing between descriptions of worlds rather than distinguishing between worlds. The options are: EITHER (1) Replace either "a mirrored version of the world" or "the mirror image of the current world" with the words "the actual world." OR (2) Explain each of the concepts clearly enough that it is possible for the reader to understand the difference between (1) and (2). — Preceding unsigned comment added by Eugene Penguin (talk • contribs) 01:08, 4 January 2015 (UTC)

Experiment Section -other way round?
In the last paragraph of the Experiment section, it is stated that:

''If the electrons were always found to be emitted in the same direction and in the same proportion as the gamma rays, P-conservation would be true. If there were a bias in the direction of decays, that is, if the distribution of electrons did not follow the distribution of the gamma rays, then P-violation would be established.''

I am maybe a bit puzzled, but isn't it exactly the other way round? In the results section, it is stated that If P-conservation were true in beta decay, electrons would have no preferred direction of decay relative to the nuclear spin, which seems correct to me but contradicts the other sentence. Nilpferd1991 (talk) 14:06, 22 October 2018 (UTC)

equal probability in all directions
The article says: equal probability in all directions. They don't have to be equal in all directions, only, as it says just a little farther down, the same for θ and pi-θ. Gah4 (talk) 06:34, 8 October 2020 (UTC)

gamma ray anisotropy?
Why does the results section say: gamma ray anisotropy instead of beta anisotropy? Gah4 (talk) 06:39, 8 October 2020 (UTC)

Diagrams
Sorry I'm late to the party. I only noticed today that you removed File:Wu experiment.jpg and suggested using a diagram like the one here (page 7) to explain the anisotropy/P-violation idea. I'd be happy to make a new image for you if you like. Just leave a note on my talk page. Cheers. nagualdesign 13:53, 16 December 2020 (UTC)

I went ahead and made the image (right). Let me know if you'd like any alterations. nagualdesign 22:11, 16 December 2020 (UTC)


 * Sorry, I've been away for quite a while so I've only just seen these messages. The new graphic looks great; well done for ignoring my silence and getting it done anyway. I can't see anything that I would want altered -- it looks fine to me. Good job. Krea (talk) 00:58, 26 March 2021 (UTC)


 * No worries. Thanks for the belated reply. And welcome back! nagualdesign</b></b> 01:13, 26 March 2021 (UTC)

Experimental measurements, two for gamma anisotropy, one for beta
The article says that "experiment then essentially counted the rate of emission for gamma rays and electrons in two distinct directions", when actually the gamma was measured in two directions ("polar" and "equatorial") whilst the beta only in one. The gamma measurements were used to measure the polarisation of the nuclei as its temperature changed as it warmed up from a very low temperature and the cold beta emissions compared with the warm ones. The latter differed much more than the former because of the parity violation. PeterGrecian (talk) 11:12, 8 April 2021 (UTC)