Talk:Muon

Muon mass[edit]

Muons have a mass that is 207 greater than the electron

Units, please. 207 what? -- Merphant

Ration bewteen quantities doesn't depend on the units and the units are given: (105.6 MeV) -- looxix 23:31 Apr 19, 2003 (UTC)

Ok, sorry, I see. -- Merphant

Is it legal to use a textbook as the source for a Wikipedia article? - ElusiveByte 20:53, Sep 21, 2003 (UTC)

Yes. Strait 16:37, 13 July 2006 (UTC)[reply]

The muon is also known as a mu meson

Historically correct, but nowadays the term meson is reserved for quark/antiquark particles. The term mu meson is now a misnomer.

Herbee 2004-02-07

muon ... is a collective name

Is that really true? IMHO muon refers only to μ^-, while μ⁺ is called an antimuon.

Herbee 2004-02-07

Generally, physicists will refer to either as a "muon." Sometimes we'll even say "positive muon" and "negative muon" for clarity. -- SCZenz 17:07, 28 August 2005 (UTC)[reply]

I would add a more precise value of the muon-electron mass ratio and muon mass in other units like daltons from CODATA. Proton, neutron and electron have their masses shown in different units in Wikipedia and muons are included in CODATA. Other particles like pions are not included in CODATA and their masses are known with much less precision than muon mass.2001:1AE9:24B:4600:C05B:E75C:FFB0:BE3A (talk) 19:58, 29 January 2020 (UTC)[reply]

Done. I did not add mass in kg because since the redefinition in 2019 there is a fixed conversion factor between kg and MeV.2001:1AE9:24B:4600:387B:91D:D61:16D3 (talk) 23:21, 1 February 2020 (UTC)[reply]

I added the mass in kilograms, for two reasons. First, the kilogram is, after all, the official SI unit of mass. Second, if you search for "muon mass" on the source that is given as the reference for the mass values, i.e. the NIST website, and (among the search results) you click on the link for "muon mass" (as opposed to clicking on the link for "muon mass energy equivalent in MeV" or "muon mass in u"), you get a value in kilograms. --Reuqr (talk) 08:06, 17 November 2020 (UTC)[reply]

Wobble[edit]

http://www.aip.org/pnu/2002/split/600-1.html

Can someone who understands this fill us in on the wobble ? Wizzy…☎ 14:52, August 28, 2005 (UTC)

I just added two external links to the main page, and I was hoping that someone that understands it better than I do would write about it or know of a link in wiipedia to more information. Bubba73 15:58, August 28, 2005 (UTC)

I understand it, but I may need to find (or draw) a picture to explain it more clearly than those pages do. I'll put it on my list. -- SCZenz 17:07, 28 August 2005 (UTC)[reply]

CERN dimuon experiments[edit]

Took out the bit about CERN doing neutrino+proton-->dimuon work. Does anybody know the actual name of this experiment, if it existed? Similar work was done at Fermilab and SLAC, but I didn't turn up anything at CERN. -- Xerxes 22:30, 5 November 2005 (UTC)[reply]

Lifespan?[edit]

Quoting from the article:

"The muons from high energy cosmic rays are often moving at very high velocities, so despite their short lifetime, the time dilation effect of special relativity...."

What exactly is the typical lifespan of a muon? Aside from the above-mentioned allusion to a "short lifetime", the article says nothing about that. 24.6.66.193 20:50, 12 October 2006 (UTC)[reply]

It's the second line of the article. Half-life 2.2 microseconds. About 660 m = .66 km at the speed of light. Which would make it tough for many muons to get down from the upper atmosphere, were it not for relativistic time-dilation. S B H arris 23:30, 12 October 2006 (UTC)[reply]

It is the subatomic particle with the second longest mean lifetime (2.2 µs), behind the neutron (~15 min)

following the link to subatomic particle, I find that the proton is considered a subatomic particle. and, following the proton link, find its lifetime is really jolly big ("Mean lifetime: >2.1×10^29 years (stable)"), so there's some contradiction here (perhaps in the terminology?) akay (talk) 14:06, 17 June 2009 (UTC)[reply]

Its the second longest amongst unstable particles. I guess we could clarify.Headbomb {^ταλκ_{κοντριβς} – WP Physics} 14:22, 17 June 2009 (UTC)[reply]

Note that it is mean, sometimes called 1/e, lifetime of 2.2us, the half life is a little less. Exactly why radioactivity started using half life so many years ago, when everything else is measure in mean, or 1/e, life, I don't know. For example, the decay constant for RC circuits is measured as 1/e, as that is what you get from the differential equation, as RC. Should the infobox also give half life? Where should this question be asked? (Do infobox for radioactive isotopes give half life or mean life?) Gah4 (talk) 01:52, 6 September 2021 (UTC)[reply]

Dirac and the muon[edit]

Somewhere in the depths of my memory, I recall that Paul Dirac, in an interview, said that he was working on a theory which would make the muon "something like" an excited state of the electron. Does anyone know any further details?

Hair Commodore 19:04, 25 October 2006 (UTC)[reply]

redirect[edit]

Does anyone know why AntiMuon redirects here?

Where else would it redirect? Or what would it say as a separate article? -- SCZenz 02:13, 30 October 2006 (UTC)[reply]

It would say the same thing as this article, but time-reversed.216.80.110.88 (talk) 01:16, 30 January 2009 (UTC)[reply]

Ratings[edit]

I noticed that this article didn't have an Assessment or Importance rating. I rated importance as "Top" (subject is a "must-have" for a print encyclopedia). I put the Assessment as B, but I would appreciate if others have a more well-formed opinion (I am new at this). By the way, I love the fabulous picture of the moon's shadow in muons. HEL 17:02, 8 December 2006 (UTC)[reply]
The opening paragraph is one of the best I have ever read in the Wikipedia. Cover up the rest of other sci-tech Wiki articles and ask, Can I leave with the basic definition, the relationship to the field, and some needed cautions about controversies or historic ambiguities? You can here. Thank you contributors and community. Jerry-va (talk) 13:40, 12 January 2010 (UTC)[reply]

This paragraph has not much (semantic) sense, specially the last two lines. —Preceding unsigned comment added by 128.227.179.188 (talk) 19:22, 6 December 2007 (UTC)[reply]

Energy paragraph unclear[edit]

"Since the production of muons requires an available COM frame energy of over 105 MeV, neither ordinary radioactive decay events nor nuclear fission and fusion events (such as those occurring in nuclear reactors and nuclear weapons) are energetic enough to produce muons. Only nuclear fission produces single-nuclear-event energies in this range, but due to conservation constraints, muons are not produced."

This paragraph is confusing. First, it says that muons are not produced in nuclear fission, then the next sentence says they are. Which one is accurate? Duckyphysics (talk) 02:47, 28 March 2008 (UTC)[reply]

Copy-editing[edit]

Uhh, this page requires some serious copy-editing. There is some duplicated stuff and a lot of random external links directly in the article. They should be screened for redundancy, importance and availability (the only one given as ref-tag seems to be dead). --Pjacobi (talk) 00:26, 13 June 2008 (UTC)[reply]

Font[edit]

Am I the only one that finds the font used for the elementary particles in text mode to be terrible? The simbol for the muonic neutrino might as well be $v_{u}$ instead of $\nu _{\mu }\,$ and I wouldn't be able to tell the difference. there's got to be a better way to do it. I would change it myself if I knew how to do it. Dauto (talk) 04:45, 18 January 2009 (UTC)[reply]

There's an ongoing discussion about that somewhere I think. I'll try to find a link, else I'll start one on Template talk:SubatomicParticle. Headbomb {^ταλκ_{κοντριβς} – WP Physics} 05:54, 18 January 2009 (UTC)[reply]

Muon Decay Diagram[edit]

Isn't the arrow depicting every anti-particle supposed to be facing the opposite direction of normal time? Please tell me if I've misunderstood something.. Thγmφ (talk) 19:42, 6 April 2009 (UTC)[reply]

Quark composition?[edit]

I do not see the quark composition anywere. This needs to be added to the article. 24.121.0.194 (talk) —Preceding undated comment added 00:03, 18 May 2009 (UTC).[reply]

That's because muons (like electrons) are leptons. They are elementary particles. Headbomb {^ταλκ_{κοντριβς} – WP Physics} 00:43, 18 May 2009 (UTC)[reply]

And yet the Wikipedia article on Elementary particles says : "Subatomic particles such as protons, neutrons or muons, which contain two or more elementary particles, are known as composite particles." 2001:569:5088:F900:ADE4:A9EB:BC19:63DF (talk) 07:28, 21 August 2023 (UTC)[reply]

Yes, that one is wrong. After Yukawa, the muon was found, and thought to be Yukawa's particle. Later the pion was found, which is the actual one. Then meson got attached to both of them. Most mesons are made of quarks, but not muons or tauons. Gah4 (talk) 07:18, 22 August 2023 (UTC)[reply]

Theory?[edit]

Is there any theory about why the muon/electron ratio is 207 and no other number? Is it an even multiple? Why can't there be a negative lepton with mass equal to, say, 100 times the electron? Or is this an unsolved problem? CharlesTheBold (talk) 03:38, 25 June 2009 (UTC)[reply]

No one has a clue why the masses are what they are, and no it's not a integer multiple (assuming you mean integer and not even multiple).Headbomb {^ταλκ_{κοντριβς} – WP Physics} 04:00, 25 June 2009 (UTC)[reply]

bremsstrahlung radiation[edit]

The word bremsstrahlung already includes the word radiation (it translates from german to "stopping radiation"), so "bremsstrahlung radiation" is redundant! Please change it to bremsstrahlung only! —Preceding unsigned comment added by Boeser wolf (talk • contribs) 17:46, 24 October 2009 (UTC)[reply]

For people who don't speak German, we need the redundancy. This is perfectly acceptable, like speaking of the WMF foundation, or a thorny Acacia tree. S B H arris 19:52, 24 October 2009 (UTC)[reply]

Or talking about the Rio grand river or GUT theory, etc... This is actually the correct way to do that kind of thing. Dauto (talk) 18:36, 13 January 2010 (UTC)[reply]

Weaponry?[edit]

In the side bar, under uses, weaponry is listed. Nowhere in the article does it elaborate, and clicking on the link takes one to antimatter weapons.

Is this "use" of muons so far-fetched or has something actually feasible been proposed? If the former, it should probably be removed, and if the latter, it should be explained.

128.95.101.192 (talk) 00:40, 13 November 2009 (UTC)[reply]

The sidebar appears to be a template with no parameters, so it's just blindly copying the template's contents without regard to the context of the current article. The use of muons as weaponry sounds very far-fetched, since in that very section, it says that the energy required to generate muons cannot be attained by nuclear reactors, and even nuclear weapons, which does attain to the required energies, does not produce muons due to other constraints. Given the difficulty of producing muons in the first place, and their short lifetimes, it seems inconceivable at the current state of technology that they can be used as weaponry.—Tetracube (talk) 00:46, 13 November 2009 (UTC)[reply]

It's the antimatter navbox. Personally I don't think it should be on this article at all. I'll remove it unless someone objects. Headbomb {^ταλκ_{κοντριβς} – WP Physics} 13:54, 13 November 2009 (UTC)[reply]

Cosmic muons[edit]

We need a section on cosmic muons and their flux. Something about momentum and angular distributions (cos2theta at zeroth order), the effect of the earth's magnetic field on different charges, etc. Erkcan (talk) 18:23, 25 January 2010 (UTC)[reply]

Nuclear Cowes[edit]

In Muon Sources paragraph "nuclear cowes - what is that? Is that a mistake? StuDreamer (talk) 10:32, 9 July 2010 (UTC)[reply]

A vandalism.S B H arris 21:15, 16 August 2010 (UTC)[reply]

Charge Radius[edit]

I am a little confused about the section on charge radius. First, wouldn't the the Lamb shift raise the muon from the 2S to the 2P state and not from the 2P to the 2S as stated in this section?

Second, it is my understanding from reading the references that the 0.841 femtometer value for the proton charge radius is significantly at odds with the previous value. By significantly at odds I meant that the previous value was known to four significant digits. The recent experimental value (quoted to three significant figures here, but given to 5 significant figures in the reference) differs from the previously accepted value in the second significant digit which seems like a large discrepancy that needs to be explained.

TedEyeMD —Preceding unsigned comment added by TedEyeMD (talk • contribs) 21:08, 16 August 2010 (UTC)[reply]

Yes, the two measurements disagree. Last I heard there was a lot of work trying to resolve the situation, but no success so far. I haven't checked lately. --128.163.7.129 (talk) 23:08, 3 February 2011 (UTC)[reply]

Pronunciation[edit]

It would be great to get information on how the word is pronounced, in the article. If anybody should describe this to me by exact comparisons with common English words, I would add a respective hint, according to the use of the international phonetic alphabet for English within Wikipedia. --Hans Dunkelberg (talk) 06:58, 13 May 2011 (UTC)[reply]

I have already been advised on how to pronounce muon, and added a respective hint to the article. --Hans Dunkelberg (talk) 07:39, 13 May 2011 (UTC)[reply]

Mean lifetime in lede[edit]

Why does the lede have "compared to that of a free neutron (~15 minutes), a free proton at greater than 6.6×1033 years (possibly infinite), and that of an electron, also possibly infinite."? Why should that comparison be made? (Is there something in the main body of the article which I missed that makes it important? This article says "They decay via the weak interaction" and the neutron article says that it's decay is "via the weak interaction"... is that the point? Why then is there such a difference in magnitude, or is that somehow unimportant/obvious?) Why is neutron not linked to the neutron article and why isn't it's mean lifetime (885.7±0.8 s via the neutron article) listed with the val template like the others? Why is the uncertainty over proton and electron lifetimes mentioned at all? -- Limulus (talk) 08:45, 17 July 2011 (UTC)[reply]

That's a lot of questions. Let me see if I can answer some of them.

Thank you for taking the time to reply :) -- Limulus (talk) 20:18, 17 July 2011 (UTC)[reply]

"Why does the lede have "compared to that of a free neutron (~15 minutes), a free proton at greater than 6.6×1033 years (possibly infinite), and that of an electron, also possibly infinite."? Why should that comparison be made?"

This is wikipedia. The comparison is there because somebody thought it might be useful.

Heh. Yes, indeed; perhaps I should have phrased the question more along the lines of 'should ... be in the lede to a Wikipedia article on muons?' ;)

I don't find the proton and electron comparisons particularly useful. The neutron, on the other hand is more valuable because it also decays through the week interaction as you pointed out.

OK, that's what I suspected, but as I don't consider myself particularly knowledgeable in particle physics, I thought I should ask before making a potentially disruptive edit. -- Limulus (talk) 20:18, 17 July 2011 (UTC)[reply]

"Why then is there such a difference in magnitude"

The phase space volume available for the two decays is very different causing the half-lives to be very different as well.

OK, hmm... if we're going to include the neutron for comparison as it is different, maybe let's also include the hyperon (mentioned here along with neutron and muon) -- Limulus (talk) 20:18, 17 July 2011 (UTC)[reply]

"Why is neutron not linked to the neutron article"

No reason. I'll create the link.

Thanks! -- Limulus (talk) 20:18, 17 July 2011 (UTC)[reply]

"why isn't it's mean lifetime (885.7±0.8 s via the neutron article) listed with the val template like the others?"

I'm not sure I understand the question.

Just a formatting question; I will take care of that. -- Limulus (talk) 20:18, 17 July 2011 (UTC)[reply]

"Why is the uncertainty over proton and electron lifetimes mentioned at all?"

As I said, this is wikipedia. Dauto (talk) 16:09, 17 July 2011 (UTC)[reply]

Hydrogen-4.1[edit]

[1] I advice Sbharris to look on sources before altering things to which he is not accustomed – sorry, but I can testify that this is not the first instance. Moreover, the article explained why this exotic atom has a hydrogen chemistry, not one of a noble gas. Incnis Mrsi (talk) 22:14, 1 March 2013 (UTC)[reply]

Yes, I see that. In that case, the WP article should carefully explain that somebody has proposed that muonic He be called H-4.1 strictly on the basis of chemical behavior, rather than physical construction (since the latter, of course, shows that it's still helium). The idea is that the muon screens one nuclear charge so it "looks like" hydrogen. But classifying things according to their chemistry results in silliness like trying to write muonium as H-0.11 (even though it's not a hydrogen atom or any kind of atom), which this source also does (I don't care if they do it-- it's not standard notation). Worse still, if you follow this train logically, muonic hydrogen must be written "n-1.1" or "neutronium-1.1" since the muon screens the proton's charge, so it looks like a neutron. Do you want to write muonic H as neutronium-1.1? Really? S B H arris 01:48, 3 March 2013 (UTC)[reply]

No, I would prefer instead to write the ⁴He⁺ +
μ⁻
composite as ⁴(H_μ×H_e) and the muonic hydrogen as H_μ, or H_μ×n_e if you prefer uniformity. Unfortunately, my notation, just like your H-0.11, is original. Hydrogen-4.1 is not. Incnis Mrsi (talk) 17:27, 3 March 2013 (UTC)[reply]

It's too original for Wikipedia. It's used in this one paper, one youtube source (perhaps by an author?) and the rest of the usage on the net is due to WP-derivative books in turn referencing this article. Which means they are from somebody (you?) sticking this reference into Wikipedia. One primary source proposing some odd usage which hasn't been picked up by the community in secondary and tertiary sources, is not enough to clutter up a primary article like muon. H-4.1 or whatever is a problem for IUPAC, not youtube or somebody fooling around in the primary literature. So, I suggest you remove it. The authors of the science paper are cute, but their usage has yet to stand the test of time. We don't put all suggestions on names from single papers in the primary physics and chem literature into Wikipedia. Sorry. Even the discoverers of new astronomical objects must have their choices ratified by the naming commission of the IAU. S B H arris 02:24, 4 March 2013 (UTC)[reply]

Roughly?[edit]

The lede currentl has "with unitary negative electric charge of roughly −1 and a spin of 1⁄2". How is this roughly? (Am I missing a process that makes its measurement not exactly -1?) RJFJR (talk) 20:56, 25 February 2014 (UTC)[reply]

Removed. The discussion pertains to elementary charge by any means. Incnis Mrsi (talk) 07:43, 26 February 2014 (UTC)[reply]

The only longer lifetime for an unstable subatomic particle is that for the free neutron[edit]

Thanks to 168.156.40.253 (talk · contribs) my attention was eventually attracted to this thoughtless crap. The people who stuck to very long particle colliders are accustomed to think that all subatomic particles are baryons, leptons, and various bosons (such as mesons, fundamental forces, and the Higgs). It is not true: there are also many unstable atomic nuclei with lifetimes, usually, much longer than of the muon. Since there is no ¹
₀n
atom, I excluded the neutron from atomic nuclei although its flavour lies in their plane. Incnis Mrsi (talk) 07:43, 26 February 2014 (UTC)[reply]

@talk To necro-bump, the content seems clear enough to me, but I fixed it. Rolf H Nelson (talk) 20:41, 17 December 2016 (UTC)[reply]

Non-ionizing?[edit]

On what possible basis can it be claimed that muons are non-ionizing radiation? Every detection method is based directly (gas-wire tubes) or indirectly (scintillators) on muons ionizing matter - so how can it be described as non-ionizing? I think the description should be removed from the section on muon radiography and tomography.198.81.129.195 (talk) 16:31, 28 October 2015 (UTC)mjd[reply]

Typo in the Muon Decay Rate Formula[edit]

In the Muon Decay section, it states

\Gamma ={\frac {G_{F}^{2}m_{\mu }^{5}}{192\pi ^{3}}}I\left({\frac {m_{e}^{2}}{m_{\mu }^{2}}}\right),

where $I(x)=1-8x-12x^{2}\ln x+8x^{3}-x^{4}$ . This obviously means $x={\frac {m_{e}^{2}}{m_{\mu }^{2}}}$

However, someone added $x=2E_{e}/{m_{\mu }}c^{2}$ , which is inconsistent with previous formula.

Louis925 (talk) 09:52, 31 October 2015 (UTC)[reply]

Quoted source does not contain the relevant information, and unclear sentence[edit]

The first sentence in https://en.wikipedia.org/wiki/Muon#Muon_sources reads "On Earth, most naturally occurring muons are created by quasars and supernovas, which consist mostly of protons, many arriving from deep space at very high energy". The given source is available online: http://www.kfki.hu/~matyasm/books/Caroll_Sean_Spacetime.pdf But I can't find the reference on p204.

Besides: I'm not sure what the aim of the sentence is and I think it is easy to misunderstand this sentence. I read the statements: 'Quasars and supernovas consist mostly of protons' and (this is how I understand the sentence) 'most muons come from deep space at very high energies'

To this I'd say: First: "mostly consist" is not defined. 'Supernovae consist mostly of neutrinos.' would be a true statement (energy wise). Second: At least it is easy to misunderstand. Imo it's wrong as it's written there.

For these reasons I have substituted the complete sentence with:

"Muons arriving on the Earth's surface are created indirectly as decay products of collisions of cosmic rays with particles of the Earth's atmosphere."

--MartinFleck (talk) 14:20, 23 February 2016 (UTC)[reply]

Muon Detectors[edit]

I came here after learning about "scan pyramids". Could something be added about Muon detectors used in scanning large structures? Maybe there's another article, don't know can't find it. Nibinaear (talk) 14:17, 5 November 2017 (UTC)[reply]

See muon tomography — dukwon (talk) (contribs) 14:41, 5 November 2017 (UTC)[reply]

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Submarine communication[edit]

Why can't Muons be used for sending orders to submarines? If this could be done, it seems like a much better mechanism vs. VLF or satellite comms.? 139.138.6.121 (talk) 08:35, 9 November 2020 (UTC)[reply]

New force in Nature[edit]

I am not a physicist, so I would not wish to edit this article myself, but should this article point out that on the BBC news on 7 April 2021, it was reported that scientists in the United States believed that they had found evidence for a new force in nature, because they observed that muons spun round more quickly than predicted? Rollo August (talk) 20:51, 7 April 2021 (UTC)[reply]

I also came here after reading this! No Swan So Fine (talk) 08:38, 8 April 2021 (UTC)[reply]

Popular press breathless hype on confirmation of previous Brookhaven unexplained result. The search is ongoing.Cuzkatzimhut (talk) 11:13, 8 April 2021 (UTC)[reply]

How are muons produced in the lab?[edit]

I can't find this information in the article.150.227.15.253 (talk) 20:32, 7 February 2022 (UTC)[reply]

it’s right there in the lede: “These interactions usually produce pi mesons initially, which almost always decay to muons.“ Cuzkatzimhut (talk) 02:23, 8 February 2022 (UTC)[reply]

Confusing (but not wrong?)[edit]

Recent edit by Muon2233 introduced a confusing sentence:

... they showed that the muons from cosmic rays were decaying within being captured by atomic nuclei, ...

I think they wanted something like "were decaying even after being captured by atomic nuclei" when that was unexpected for the Yukawa particle? But I am not a physicist and such text makes me happy about that.

Farther on in the article there is:

The difference, in part, was that mu mesons did not interact with the nuclear force, as pi mesons did (and were required to do, in Yukawa's theory).

And surrounding commentary might help rewrite the confusing sentence. Shenme (talk) 19:20, 24 February 2023 (UTC)[reply]

Sorry there is indeed a typo in the sentence I introduced, I meant "...they showed that the muons from cosmic rays were decaying WITHOUT being captured by atomic nuclei...". This is indeed consistent with the later sentence. Muon2233 (talk) 20:29, 24 February 2023 (UTC)[reply]

Pronunciation (bis)[edit]

The first sentence gives the pronunciation as /ˈm(j)uːɑːn/ , implying that the /j/ is optional. Does anyone really pronounce it without the /j/? "Moo-on"? That would sound really peculiar to me. --Trovatore (talk) 21:08, 12 November 2023 (UTC)[reply]

I believe it isn't so rare, but never tried to count. Gah4 (talk) 23:02, 12 November 2023 (UTC)[reply]

Mu_(letter) also has the optional /j/, and I suspect most people say it the same way, with on added. Gah4 (talk) 23:05, 12 November 2023 (UTC)[reply]

Hmm, /muː/ also strikes me as really odd for the letter, but I do think I've heard it. I wonder whether it varies by English variety? Normally yod-dropping is most common in American English, but /muː/ definitely does not sound American. --Trovatore (talk) 00:55, 13 November 2023 (UTC)[reply]

Mu isn't an especially common English word. Now that you mention it, I notice more often adding the /j/ to words that normally don't have it, such as moon. It does seem like English variety, though maybe not the usual regional accent. It reminds me of a Feynman story, where he was going to a conference in, if I remember, Italy, and didn't remember where it was. He asked the cab driver is other riders were discussing gee mu nu, and if so, to take him to the same place they went. If you are using both mu and nu together, it seems to be hard to say them differently. In any case, I don't know how many say each one, each way, and especially not moon, but it seems that some do. Gah4 (talk) 15:36, 13 November 2023 (UTC)[reply]

Contradiction?[edit]

The article says "the mass difference between the muon and the set of its decay products is small, providing few kinetic degrees of freedom for decay." but the most common muon decay products are an electron and neutrinos. Mass of an electron is 1/200 of a muon and neutrinos can't clearly fill the gap in mass difference unless there are millions of them so this sentence doesn't seem right. Or I'm missing something super obvious? (e.g. the energy difference is high if you compare to their mass but it's still small? 200MeV is not small though) Ladsgroup^overleg 00:00, 27 November 2023 (UTC)[reply]

Is this statement about charged lepton decay correct?[edit]

Re the following statement, which appears just above subsection "Muonic atoms":

 "More generally in the Standard Model, all charged leptons decay via the weak       interaction and likewise violate parity symmetry."

Electrons are charged leptons, but according to [1] are thought to be stable.

Is there some subtlety here that is not mentioned or perhaps taken for granted that the reader appreciates? I am very far from expert in this topic, but it was unclear to me, perhaps to others as well, how this statement could be entirely accurate exactly as written.

[1] https://en.wikipedia.org/wiki/Electron Phlegman9 (talk) 00:45, 20 February 2024 (UTC)[reply]