Talk:Axion

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axion

Apparantly found: http://www.physorg.com/news84633896.html anescient 19:35, 6 December 2006 (UTC)

Primary: http://www.iop.org/EJ/abstract/0954-3899/34/1/009 ~Kylu (u|t) 04:18, 7 December 2006 (UTC)

Physorg.com is a website of dubious credibility, and the press interpretation of this paper is generally sensationalist. These are probably not axions! 18.4.2.3 17:31, 7 December 2006 (UTC)

I raised the importance level of this article to Medium. Axions are of intense theoretical and experimental interest. They are related to Strong CP Violation which, in turn, relates to the observed matter / antimatter asymmetry of the universe (or Baryon number problem). They are also possibly important for other cosmological effects. Finally, we may be able to experimentally observe them.

Slashdot backs things up. http://science.slashdot.org/article.pl?sid=06/12/06/2212250&from=rss Believe it now? --//Mac Lover TalkC 01:44, 10 December 2006 (UTC)

Umm... maybe you're kidding, but Slashdot is not a reliable source of information on scientific subjects. --Reuben 07:54, 10 December 2006 (UTC)
Does anybody else has proof about axions?--//Mac Lover TalkC 03:02, 12 December 2006 (UTC)
No, axions are still hypothetical particles. Nobody has demonstrated that they exist so far. There are a couple of promising leads (see the article), and other searches in progress, so maybe someday there will be proof of axions - but not now. --Reuben 04:51, 12 December 2006 (UTC)

[edit] Please explain in the article!

How is this thingie different from the various kinds of neutrinoss? Both are chargeless, very light and minimally interactive with matter. 195.70.48.242 09:53, 7 December 2006 (UTC)

Among other reasons: Given that the decay spectrum of the supposed axion is e+e-, the axion must be a boson (and as an effective degree of freedom from chiral condensate it could hardly be anything else). The neutrino is a spin-1/2 fermion.

Well yeah, what the person above said. The axion is a spin-0 boson, the neutrino is a spin-1/2 fermion. The axion holds a very different place in the overall theory of all the particles than the neutrino (by overall model I mean the Standard Model). See the wikipedia page for "List of particles"

[edit] Jain

I have to disagree with removal of the paragraph about Jain's supposed discovery.

  • The press release is no longer available on U Buffalo web site, but the original article used by PhysOrg is still there: [1]
  • What exactly does Jain/Singh paper claim? Literal quote: "the persistent appearance of unusual narrow peaks around Q = 7 ± 1 MeV and 19 ± 1 MeV favours the existence of new short-lived exotic particles." In the very next paragraph: "The present experiment sheds some light on why the numerous previous efforts over more than two decades were not successful in detecting the low-mass, neutral, short-lived nonstandard axions." The word "axion" appears in the article 6 times, and no other possible short-lived exotic particles are mentioned. So they may not claim explicitly that they have discovered the axion ( their data is simply not good enough to make such claims ), but they sure do imply it. --Itinerant1 01:54, 8 December 2006 (UTC)


This can't possibly be the axion. If it were a particle it must show up as a narrow peak in Fig.2(a) due to the claimed lifetime in Fig.1(a). The width of a particle in the Q graph is 1/lifetime, and the claimed lifetime is so large that it's width must be tiny -- literally a line on the graph (smeared by detector resolution). But instead Fig.2(a) is totally smeared out. This must be some off-shell phenomena or fakes. It is not a particle.

Also, the standard for claiming discovery of a new particle is 5 standard deviations. The reason for this is because we often see fluctuations below this that go away with more data. The small peaks he does claim after massaging his data are only three standard deviations.

So, the claim that it's a particle is dubious. The claim of a discovery is absolutely wrong. This does not meet the criteria for a particle discovery in particle physics. 164.156.227.2 18:18, 8 December 2006 (UTC)

Axion is also the name of a series of tractors for agrivultural use by geman (combine-)manufacturer Claas.