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Tiny Particle With No Charge Discovered
Posted by
ScuttleMonkey
on Wed Dec 06, 2006 05:36 PM
from the met-with-a-neutral-response dept.
from the met-with-a-neutral-response dept.
ZonkerWilliam writes to mention PhysOrg is reporting that a tiny particle with no charge called an 'axion' has been discovered. From the article: "The finding caps nearly three decades of research both by Piyare Jain, Ph.D., [University of Buffalo] professor emeritus in the Department of Physics and lead investigator on the research, who works independently — an anomaly in the field — and by large groups of well-funded physicists who have, for three decades, unsuccessfully sought the recreation and detection of axions in the laboratory, using high-energy particle accelerators."
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What did the bartender say to the axion? (Score:5, Funny)
Re:What did the bartender say to the axion? (Score:5, Funny)
Don't be confused. This particle has no charge, it's free as in beer.
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Re:What did the bartender say to the axion? (Score:5, Funny)
The police say "Are you sure?"
And the atom replies...
"Yes! I'm positive!"
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Re:What did the bartender say to the axion? (Score:4, Funny)
In the box with or without the cat.
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Re:What did the bartender say to the axion? (Score:4, Funny)
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Re:What did the bartender say to the axion? (Score:4, Informative)
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Won't hold a charge... (Score:5, Funny)
No Charge eh? (Score:4, Funny)
Anyways, pretty good!
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and it means... (Score:4, Informative)
Re:and it means... (Score:5, Funny)
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Re:geek language (Score:5, Funny)
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They find an axion?? (Score:3, Funny)
Re:They find an axion?? (Score:5, Funny)
BTW, and they would need about $10000000000000000000 funding for LEC (Large Earth Collider).
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Re:They find an axion?? (Score:5, Funny)
BTW, and they would need about $10000000000000000000 funding for LEC (Large Earth Collider).
About the same requirements as the US military then, eh?
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Funding (Score:5, Funny)
Dear Sir,
Your proposal intrigues us. If you can flesh it out with further details, we are certain that a mutually satisfactory agreement can be reached. Eagerly awaiting your reply.
Sincerely Yours,
Galactus, LEXX, and Prostetnic Vogon Jeltz
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Detected... (Score:3, Interesting)
Re:Detected... (Score:5, Informative)
"They didn't know how to handle the detector for short-lived particles," Jain said. "I knew that for this very short-lived particle -- 10-13 seconds -- the detector must be placed very near the interaction point where the collision between the projectile beam and the target takes place so that the produced particle doesn't run away too far; if it does, it will decay quickly and it will be completely missed. That is what happened in most of the unsuccessful experiments." Instead, Jain used a visual detector, made of three-dimensional photographic emulsions, which act as both target and detector and that therefore can detect very short-lived particles, such as the axion. However, use of such a detector is so specialized that to be successful, it requires intensive training and experience. In the 1950s, Jain was trained to use this type of detector by its developer, the Nobel laureate, British physicist Cecil F. Powell. Jain has used it throughout his career to successfully detect other exotic
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Re:Detected... (Score:5, Insightful)
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Re: (Score:3, Informative)
Think of it like those high speed film clips of a bullet going through a block of ballistics gel. The particle hits the emulsion and leaves a detectable wake.
Re:Detected... (Score:4, Insightful)
This is a bad description. The wake of a bullet going through ballistics gel is due to the electromagnetic force. The axion, in contrast does not experience that force. Like the neutron, it must be discovered indirectly (though it is more difficult to discover than a neutron). A useful part of the article:
So basically, they discovered it by observing the electrically interacting positron and electron pair produced very close to the production with a specialized type of photographic film.
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Re:Detected... (Score:5, Informative)
And the Universe is powered by stupidity. The wake of a bullet going through ballistics gel is caused by the shockwave of the bullet's impact with the surface of the gel; a bullet is not a charged particle, nor magnetic, and it's way to big to create the ionization effects that traditional particle detectors use. I don't know how it is possible that, not only could say that a bullet causes a wake due to electromagnetic force, but that a mod actually believed that bullshit.
I hope this is a good learning experience for you and I hope that you don't recklessly call other posters stupid next time.
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Re:Detected... (Score:4, Insightful)
I don't really care that it bothers you that I have simplified this to the simplest case (but as Einstein would suggest "no simpler"). Sure you can describe the perturbation of a ballistics jell with forces that are composed of special cases of the electromagnetic force but the fundamental point is that without the ability to interact electromagnetically at the lowest level all of those forces result to zero.
If an axion has a zero fundamental charge you can talk about impulses all night long but they still do not mean a damn thing. When you discuss subatomic particles you cannot use the special cases of the forces that we have come to love (because they make our lives simple). Spring constants have no meaning. Pressure has no meaning. Even things like angular momentum take on bizzare new forms that cannot use the classical theories.
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Re:Detected... (Score:5, Insightful)
The wake is due to the transfer of kinetic energy from the bullet (okay, the bullet as measured from the frame of the gel) to the gel (in it's frame). Electromagnetics is just the medium of this transfer.
A bullet sitting motionless in gel creates no wake... but the electromagnetic force is still there.
Clearly, the wake is not "due" to the electromagnetic force, it is a "product" of said force (and the kinetic energy of the speeding bullet).
I applaud your mischievous wordplay, and I await the potential wrath of your advanced physics knowledge.
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Re:Detected... (Score:4, Informative)
The point that I was trying to make is that a zero charge particle doesn't interact electromagnetically so we can't use conceptual examples that involve the electromagnetic force regardless of how trivial to describe it. There do exist many particles that do interact electromagnetically and you could say they travel through a medium (such as a bubble chamber [wikipedia.org]) like a bullet through a ballistics jel. Heck, I've even seen the extreme examples of this where I was able to observe Cherenkov radiation [wikipedia.org] from a nuclear reactor's fuel elements (where a charged particle moves faster than the speed of light in that medium producing a really pretty blue light).
But the axion itself does not interact electromagnetically so by itself it does not produce a wake. The electron and positron produced will certainly produce wakes, but that point needs to be pointed out explicitly. The axion is not detected directly from electromagnetic interactions, only its decay products are (which are released symmetrically around the axis of the axion).
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This is a big deal (Score:4, Interesting)
Re:This is a big deal (Score:5, Funny)
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Re: (Score:3, Insightful)
Uhm, no. The Big Bang is a theory, but people don't go around trying to create mini universes. Sure you could argue that they "test" it with observational data, but that's not really performing experiments either now is it?
And as a Mathematician, why are you limiting the concept of a "theory" to the land of science? You scientists are constantly being bound by the restrictions of the physical world around you!
Isn't it one of the basic rules of grammar that if you are asking a question, you use a questio
Re:This is a big deal (Score:4, Insightful)
String theory doesn't predict anything. Its not testable. Its not science. Its caused some interesting advances in math to solve certain aspects of it, but thats about it.
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Re:This is a big deal (Score:5, Informative)
that is in the plancks (need a atom smasher as big as the solar system) mass range. String theory does have axions in it as well
as stacks of light neutral particles called moduli. The article didn't say how they knew or why they thought that particle was an
axion. The experiment found at light neutral particle with mass ~19 Mev (or maybe 7 Mev) that decays to electron positron pairs, they didn't say the had a spin measurement, if its not spin 0 with negative parity its definitely not an axion. Another experiment (PVLAS) last year found evidence a particle with mass in the milliEv range, that fits more with an axion. So maybe this is something
else.
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Re:This is a big deal (Score:4, Informative)
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Wiki (Score:5, Informative)
Called "axion"? (Score:3, Funny)
Cool that he had to use an analog detector (Score:4, Interesting)
I think it's kind of a neat ironic twist that he needed to use an analog detection mechanism to position the detector close enough to the target to detect the particle.
Re:Cool that he had to use an analog detector (Score:4, Informative)
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They say the axion has no charge? (Score:5, Funny)
I for one, do not welcome our new Overlords (Score:5, Funny)
true? (Score:5, Insightful)
This would be very important, if true. However, there's at least one thing that makes me wonder whether it's right:
Jain has used it throughout his career to successfully detect other exotic phenomena, such as the charm particle, the anomalon, the quark-gluon plasma and the nuclear collective flow.
I used to do low-energy nuclear physics research, and although this stuff is at higher energies, a lot of it sets off my B.S. detector. The information I've been able to find about the anomalon makes it sound like it's flaky. The statement in the article also makes it sound as if Jain discovered the other things on the list, but actually I think what it really means is that he participated in experiments, where his contribution was that he did the emulsion technique. From what I know about the continuing work on the quark-gluon plasma, it's not a specific, definite, yes/no thing that can really be considered to have been discovered, and I don't think emulsions have been particularly important in that work, either.
It's unfortunate that the paper isn't available on arxiv.org. However, IOP will let you read it if you set up an account. Well, I'm not a specialist in relativistic heavy ion physics, or emulsion techniques, but the paper doesn't look very convincing to me at all. In figure 4, they claim to see two peaks, one near 7 MeV, and one near 19 MeV. The statistics simply don't look convincing. All I see is a spectrum with some noise in it, where they've picked what look like two big statistical fluctuations and called them peaks. They claim it's significant at the 3-sigma level, which actually isn't a very high level of statistical confidence, especially for such an extraordinary claim.
Re:true? (Score:5, Funny)
This is a
Parent
Re:true? (Score:5, Insightful)
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.
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Three Decades!!! (Score:3, Interesting)
30 years.
10,957 days.
262,968 hours.
15,778,080 minutes.
946,684,800 seconds of your life.
All to find a virtually infinitesimally particle with no charge at all.
That, and mention on Slashdot: Priceless!!
Particle physics news usually gives me a charge... (Score:4, Funny)
Tiny Particle With No Charge Discovered (Score:5, Interesting)
Re: (Score:3, Funny)
Re:Tiny Particle with no charge? (Score:5, Informative)
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Neutrino, maybe, but not neutron. (Score:5, Insightful)
Actually, now that you mention it, wouldn't a neutrino qualify?
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Re: (Score:3, Funny)
Re:Long Lived Axions (Score:4, Informative)
Most models for axions are much lighter and have much weaker interactions, giving them much longer lifespans. That's what's being described in the article you cite. An axion with those properties would be an ideal candidate for dark matter - tons of them would fill the universe, and they'd be nearly undetectable due to their weak interactions.
Most searches for axions focus on the longer-lived possibilities for this reason, so far with no success. I'm intrigued if this claim is true, but I'll wait to see what other physicists think.
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Re: (Score:3, Informative)
No, neutrons have a neutral charge -- that is, that their net charge is neither positive (+) nor negative (-). But they have a charge. Protons have a net positive charge, electrons have a net negative charge and axions have absolutely no charge at all.
Re:It makes perfect sense (Score:4, Interesting)
That an independent researcher would headline something like this, rather than some "well-funded" group. How could you ever write a grant to research something that is free of charge?
Hee hee...
...but seriously, one of the things that smells really fishy about this is that there are only two authors on the paper. Relativistic heavy-ion physics is a field that normally involves huge collaborations. You get maybe 50 or 100 authors on every paper. There's just no possible way, politically, that these two American guys could submit a proposal to CERN, do an experiment, publish results showing physics beyond the standard model, and not have any other names on the paper. If physicists at CERN believed the result, you'd better believe that some of their names would be on it.
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Well gee I'm not a physicist, but... (Score:4, Funny)
Are you sure you heard this from a real source? Are you sure that maybe you didn't get drunk and pass out while your television was playing DRAGONBALL Z RERUNS?
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