Talk:Kaon

History of the discovery of parity violation moved
The history of the discovery of parity violation has been moved from this article to that. Bambaiah 13:28, Jun 19, 2005 (UTC)

Is the list of quarks in each kaon correct?
Is the list of quarks in each kaon correct? I can't get the charge to work out. I believe the correct listing is:

K+: strange antiquark, up quark

K-: strange quark, up antiquark

K0: strange antiquark, down quark

K0bar: strange quark, down antiquark — Preceding unsigned comment added by 202.173.128.90 (talk) 11:47, 9 September 2005 (UTC)


 * This is indeed correct. — Preceding unsigned comment added by 84.42.140.118 (talk) 12:44, 15 February 2006 (UTC)

Kaon decay
I'm pretty sure that most decay products at the list "properties of kaons" where leptons are involved are wrong. For example where it says K+ decays into mu+ and the mu-antineutrino. This can't be right since both have a lepton-number of -1...

- Jakob R —Preceding unsigned comment added by 212.114.238.93 (talk) 14:25, 27 March 2009 (UTC)

mean squared charge radius ?
What's a "mean squared charge radius"? Can we link it to something? RJFJR (talk) 22:26, 11 November 2008 (UTC)
 * It is what most people call size or radius, but quantum particles are fuzzy. Gah4 (talk) 04:13, 10 January 2023 (UTC)
 * And yes it would be nice to link it to something. Well, we should also link to Fourier transform, as that is how they are measured. Gah4 (talk) 21:11, 1 March 2023 (UTC)
 * And yes it would be nice to link it to something. Well, we should also link to Fourier transform, as that is how they are measured. Gah4 (talk) 21:11, 1 March 2023 (UTC)
 * And yes it would be nice to link it to something. Well, we should also link to Fourier transform, as that is how they are measured. Gah4 (talk) 21:11, 1 March 2023 (UTC)

K_L and K_S
These are strictly speaking not eigenstates of anything (they are not stable particles) but propagating states. Also, the quark makeup that is listed is for the CP eigenstates K_1 and K_2, which is only approximately equal to the propagating states K_L, K_S. —Preceding unsigned comment added by 129.240.86.72 (talk) 16:40, 10 June 2009 (UTC)

"Kappa meson" or "kappa particle"
Unless I am mistaken, the term kappa meson (κ-meson) was the historical designation for this set of particles. This was for consistency with the convention of using Greek letters for particles, such as α-particle, β-particle. The term seems to have fallen into desuetude, but is still occasionally encountered. I am guessing that κ was replaced by K because the Greek LC glyph and the the Latin UC glyph are visually nearly indistinguishable, not to mention the fact that the study of classical languages has fallen away. The π-meson (pion) seems partially to have escaped this fate; and the μ-meson (muon) is no longer classified as a meson at all.

Anyway, I think the synonym at least deserves a redirect and a note in the article. Not so?

--Ziusudra (talk) 19:36, 22 November 2009 (UTC)


 * Got a reference for this? Headbomb {{{sup|ταλκ}}κοντριβς – WP Physics} 23:29, 24 November 2009 (UTC)


 * I don't know when the term was proposed or the particle discovered, but it may have been by Glashow & Weinberg. I seem to remember hearing about "pi mesons" and "kappa mesons" in a physics class in 1961, but memory can play tricks.  For a historical use, see Peter Hertel's "On the lifetime of the kappa meson", Zeitschrift für Physik Volume 211, Number 5 / October, 1968, reprinted 2005 by Springer Verlag. A reference apparently dating from 2003 is found here.  Finally Dictionary.com defines "kappa-meson" as "noun: an unstable meson produced as the result of a high-energy particle collision [syn: kaon]".  --Ziusudra (talk) 15:16, 25 November 2009 (UTC)

Hadron overhaul
Please give input at Talk:Hadron. Thanks. Headbomb {{{sup|ταλκ}}κοντριβς – WP Physics} 02:00, 24 January 2010 (UTC)

Neutral kaon mixing
The K0 K0bar mixing diagram is wrong. K0 is down antistrange. They're labeled backwards, contradicting their quark content stated in the table at the top of the page. Zestfulclough (talk) 10:51, 23 May 2010 (UTC)
 * Indeed. I changed the caption to match the diagram, but it should really be the diagram that gets changed (and the text reverted) —Preceding unsigned comment added by 88.104.54.248 (talk) 01:31, 17 June 2010 (UTC)
 * A recent edit exchanged sum and difference. As well as I know, either is fine but needs to be consistent. Does someone know about this? Gah4 (talk) 21:17, 1 March 2023 (UTC)
 * Conventions of Griffiths textbook. The original was a mishmash of Griffiths conventions and Li & Cheng conventions.  I believe it is all consistent now.Cuzkatzimhut (talk) 10:45, 2 March 2023 (UTC)
 * A recent edit exchanged sum and difference. As well as I know, either is fine but needs to be consistent. Does someone know about this? Gah4 (talk) 21:17, 1 March 2023 (UTC)
 * Conventions of Griffiths textbook. The original was a mishmash of Griffiths conventions and Li & Cheng conventions.  I believe it is all consistent now.Cuzkatzimhut (talk) 10:45, 2 March 2023 (UTC)

Mixing
Either the description of the two eigenvectors Ksub1 as the sum of two states and Ksub2 as the difference appears to be contrary to that shown in the table entitled Properties of Kaons in the Basic Properties section; or the later suggestion that KS=K1 and KL=K2 is the wrong way around. Which way should it be? George963 au (talk) 16:48, 9 September 2010 (UTC)

So, what exactly are the Short and Long Kaons consistant of?
The diagram isn't highly descriptive.69.49.67.164 (talk) 01:06, 1 February 2013 (UTC)

Kaon Condensate
Could anyone please add a discussion of kaon condensates in neutron stars? Thanks. JCNSmith (talk) 18:23, 25 February 2015 (UTC)

Confusing or inaccurate
I know very little about particle physics, so I'm sure there's much I may not understand. However, to my layman's eyes, this seems either especially confusing or problematic:

"K+ (antiparticle of above) positively charged (containing an up quark and a strange antiquark) must (by CPT invariance) have mass and lifetime equal to that of K−. The mass difference is 0.032±0.090 MeV, consistent with zero. The difference in lifetime is (0.11±0.09)×10−8 s."

This explicitly tells us that the K+ antiparticle MUST have a mass and lifetime EQUAL TO that of the K-, and also that it DOESN'T. I'm not sure what it means to say that 0.032±0.090 MeV is "consistent with zero." Now, I can guess—but it is only a guess—that what I'm seeing here is an observed value being compared to a theoretical expectation, and that the small observed difference is being treated as "consistent with zero" because it could be within some margin of error for observation. However, there's nothing written here to support such a guess. On the face of it, X = Y, and X /= Y. Help! (Unless, of course, this is meant to hint that CPT invariance is wrong... if THAT's the case, then help again! Make it clear and explicit).zadignose (talk) 05:25, 16 July 2015 (UTC)

P.S., the phrasing we have now reads like the kind of phrasing that results from a feud, as though some editor presented a simple statement, then another editor felt it was necessary to point out something that challenged the validity of CPT invariance, then another editor wanted to point out that the discrepancy is too small to pose a challenge, or something of that sort. The result is unsatisfactory (unless I've completely misinterpreted it).zadignose (talk) 05:29, 16 July 2015 (UTC)


 * If you have 1±2, that means the values can be anywhere between -1 and +3. This would be something 'consistent with 0'. So if you have 0.032±0.090, then the values can be anywhere between -0.058 and +0.122. This also is consistent with 0. A result not consistent with 0 would be something like 0.34+0.02, or anywhere between 0.32 and 0.36. Headbomb {talk / contribs / physics / books} 05:48, 16 July 2015 (UTC)

Excited Kaons (K-stars)
There are a buttload more kaons than the ones listed in the article. They should at least be mentioned. See for a list. (Yes, WP:DIY. I'll do it if I get round to it.) — dukwon (talk) (contribs) 21:00, 6 May 2017 (UTC)

Would it be possible to add a Kaon sub-particle diagram similar to Pion, and Proton, which I found in simple Wikipedia. It has a blue U and yellow S bar circles on a larger circle. Have this added under the properties table on the right hand side of the page?

Low asterisk changed, even the edit comment broke on it!
The article featured a Unicode "low asterisk", which does not show up in most fonts I have access to (Chrome, Win7, not even Arial has it), and there's no reason to use a weird asterisk when * works perfectly fine.

So I replaced the little guys with *, but including the Unicode low asterisk in the edit comment apparently broke the edit comment, too. This makes it unclear why I made the edit in the first place, so I'm posting this here for reference.

Maybe we should not use weird Unicode symbols without sufficiently strong reason and compatibility testing. TricksterWolf (talk) 20:00, 8 December 2020 (UTC)

particles, antiparticles, and browsers
In my browser, and  look the same. I don't know if it is the browser's fault, or s fault. Gah4 (talk) 04:18, 10 January 2023 (UTC)