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Science

SELEX at Fermilab Discovers New Particle 259

sellthesedownfalls writes "Scientists at the Department of Energy's Fermi National Accelerator Laboratory will announce on Friday, June 18 the observation of an unexpected new member of a family of subatomic particles called 'heavy-light' mesons. The new meson, a combination of a strange quark and a charm antiquark, is the heaviest ever observed in this family, and it behaves in surprising ways -- it apparently breaks the rules on decaying into other particles. See the Fermilab Press Release."
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SELEX at Fermilab Discovers New Particle

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  • 118? (Score:1, Interesting)

    by briglass ( 608949 ) on Friday June 18, 2004 @04:04PM (#9466435)
    Who were those guys that faked the discovery of a heavy element?
  • Re:False Alarm (Score:5, Interesting)

    by Anonymous Coward on Friday June 18, 2004 @04:11PM (#9466528)
    allegedly true story:

    when CERN finished the construction of LEP, back in the day, they had a problem when they turned it on. the beam wouldn't align to collide and they had no idea why.

    upon further inspection, the problem was (allegedly) caused by a bottle of Heineken left behind in one of the beam tubes by a construction worker...
  • A good quote (Score:5, Interesting)

    by heyitsme ( 472683 ) on Friday June 18, 2004 @04:12PM (#9466541) Homepage
    I was just reading my copy of Fermilab Today (I am writing this from the lab) and saw this article. Then it appears on slashdot!

    The best description of this phenomenon comes from James Ross in the official press release [fnal.gov]:

    • "It's like watching a water bucket with a large hole and small hole in the bottom," Russ said. "For some reason, the water is pouring out the small hole six times faster than it's coming out of the large one. Something unusual must be going on inside the bucket."
  • by jwkane ( 180726 ) on Friday June 18, 2004 @04:26PM (#9466697) Homepage
    Obviously any experiment that yields unexpected and reproducable results is great news for quantum theorists.

    I'm wondering if the theoretical predictions presented in the article tip the scales toward or away from any of the various theories of quantum structure. In particular:

    "SELEX also saw the new meson decay about six times more often than expected into an eta particle (a rarer but well-studied member of the meson family), rather than into the expected particle, called a K meson."

    It seems obvious that this experiment highlights a failure in our understanding of the strong force.
  • by Anonymous Coward on Friday June 18, 2004 @04:35PM (#9466798)
    "It's like watching a water bucket with a large hole and small hole in the bottom," Russ said. "For some reason, the water is pouring out the small hole six times faster than it's coming out of the large one. Something unusual must be going on inside the bucket."

    If you follow that anology, the small hole may have a whirlpool giving it the speed advantage.

    Kinda like spinning water in a 2L coke bottle and then turning it upside down. The water falls out much faster than the big hole doing the ol glub glub.

    Its a displacement thing.
  • by Anonymous Coward on Friday June 18, 2004 @04:48PM (#9466912)
    Science really is just curve fitting. That is why the undergrads at Caltech use a program called "CurveFit". http://www.ligo.caltech.edu/~vsanni/ph3/ [caltech.edu] (CurveFit is near the bottom of the page.) Science doesn't require absolute truth, only successive approximations basedon empirical knowledge (or 'experience' in plain English). The idea that you can know absolute truth - and the need to prove yourself right when you don't know what you are talking about - are carry-overs from classical philosophers, such as Aristotle who got the rules of gravity wrong because he rested his case on only one experiment (the feather and the rock experiment).
  • by Rob Carr ( 780861 ) on Friday June 18, 2004 @05:15PM (#9467289) Homepage Journal
    I'm wondering if the theoretical predictions presented in the article tip the scales toward or away from any of the various theories of quantum structure.

    For any quantum theory [QT] there exist a range of possible values for the arbitrary constants in the theory that will account for all observed data.

    Should there fail to be a range of possible values that are consistent with reality, then there is almost certainly some form of "renormalization" which will accomodate the observations.

    Should there fail to be constants and renormalizations which give the proper results, then the problem lies with perturbation methods used to calculate the answer and a different method of calculation will need to be used, probably invoking the "small diameter dimensions, multiple string windings/large diameter, single string windings" trick.

    While we're mentioning "rolled-up dimensions," claiming that one of the additional dimensions is near-macroscopic (i.e. a hundredth of a millimeter or so) is at the very least a wonderful stalling tactic.

    Should all of the above fail, how the hell did you get tenure in the first place?

    Most quantum theories cannot be distinguished by anything less than smashing two galactic-center sized black holes together at approximately 99.857% of the speed of light. Even then, about half of the theories can be tweaked to surive the data - more than the experimenters would likely achieve.

    Someone's in a dismal mood today....

  • by Noren ( 605012 ) on Friday June 18, 2004 @05:26PM (#9467399)
    Cosmic rays from space can indeed be much more powerful than those created in particle accelerators- the seminal example is one of the few cosmic rays which has a name- the "Oh-My-God" particle [fourmilab.ch] (So named because of the exclamation the physicist was said to have made when he saw the data.) This cosmic ray had roughly 300 million times the energy of the protons Fermilab is able to produce, and was travelling at about v = 0.9999999999999999999999951 c.

    The really interesting part is that we don't really know what process would produce such a thing. Since then, several other cosmic rays [sciencemag.org](subscription required) entering the atmosphere with energies over 10^20 eV have been detected by Japanese, Russian, and American observers.

  • Re:Stupid question! (Score:5, Interesting)

    by Bingo Foo ( 179380 ) on Friday June 18, 2004 @05:29PM (#9467431)
    If by "in nature" you mean "in Yosemite and Yellowstone and on Mounts Fuji and Kilimanjaro" then no. But are there violent, high-energy events in astronomical circumstances in which these particles would be briefly found? Yes. By "discovering" the particles in the lab, they mean that they are discovering that nature works in such a way as to allow those particles to exist and have those mass/lifetime properties.

    BTW, even if there were particles which only existed in the high energies of the big bang and for 10^(-20) seconds afterwards, producing them in a hypothetical super-accelerator would still constitute a "discovery" rather than a creation or invention.

  • by lildogie ( 54998 ) on Friday June 18, 2004 @06:09PM (#9467878)
    > While the SELEX experiment stopped taking data in 1997,
    > an extended analysis revealed this new particle lurking
    > within their data.

    Nice to see the costly technology paying off long after the experiment is over.

    Pure science is worth the money.
  • "Contradiction" (Score:3, Interesting)

    by e.m.rainey ( 91553 ) <`erik' `at' `rainey.name'> on Friday June 18, 2004 @07:03PM (#9468394) Homepage
    I dislike their frequent use of the word. It seems to imply that this field is somehow solid in it's knowledge of how these particles work, when in reality it's really alot of clever guesswork. It would seem to me that what they mean by contradiction is merely a seeming contradiction because our assumptions, obviously, have come into question. I know it'd be a pain to be so annoying accurate all the time but could quantum science, in general, please qualify this more often?

    Be a little less quick to assume you're unraveling reason itself and start recognizing that if you have a contradiction, then it's because some premise of yours is wrong.
  • by barawn ( 25691 ) on Friday June 18, 2004 @08:14PM (#9468983) Homepage
    The really interesting part is that we don't really know what process would produce such a thing.

    Actually, it's worse than that. Not only do we not know what process would produce such a thing, we don't know how it would've gotten here in the first place. Above 6 x 10^19 eV, particles should interact with the microwave background, and lose energy (the "GZK cutoff"). In essence, there's a cosmic speed limit. The only way that particle could've gotten here is if it came from very close (so it didn't have time to slow down yet) - very close. Which makes the problem of "how the heck was this made?" even worse.
  • by Rob Carr ( 780861 ) on Friday June 18, 2004 @09:19PM (#9469372) Homepage Journal
    If you can allways tweak the theory to conform then it's a crap theory cause it's not falsifiable.

    Not false, but not true.

    Honestly, I was being a little humorous in my original message. But I wasn't completely accurate.

    There are places where the "Standard Model" should break down that we might be seeing pretty soon. There's even some evidence we're seeing cracks in the Standard Model, but pretty much everyone wants to see something a bit more significant.

    The problem is, we know the Standard Model cannot be correct. General Relativity and Quantum Mechanics simply do not get along as both are currently formulated. The so-called "string" and "brane" theories have features that seem to make the relativity problems go away. But there are so many different possible theories, there's no current way to tell which is correct.

    So why play with them?

    Brian Greene points out in The Elegant Universe [amazon.com] that a lot of the current theories appear to complement one another - they may in fact be subsets of the "ultimate" theory. There are some questions that one theory can answer better than another theory, and some calculations that simply can't be done in a third theory that a fourth theory handles almost trivially.

    So the physicists play with these theories in the hopes that either a) they'll find something we can test (like "large" hidden dimensions. [vub.ac.be]

    And who knows? Some folks suspect that eventually they'll find that only one theory, with only one set of constants, produces a totally consistent theory and that the current universe is the only one possible. Others postulate that we'll find there's an infinite set of possible universes with the same or similar theories, but variables that are random and that our "universe" is merely one of many in the "multiverse."

    In the meantime, it's great fun and keeps physicists employed.

  • Re:Rules (Score:3, Interesting)

    by Catharsis ( 246331 ) on Friday June 18, 2004 @09:47PM (#9469588) Homepage
    Perhaps there will always be weaknesses in theories to explain weaknesses in older ones, ad infinitum.

    Reference: Godel's Incompleteness Theorem.

    And, to quote Doug Adams:
    "There is a theory that states once we figure out exactly why we are here, that the universe will cease to exist and be replaced by something even more complex and confusing.

    There is another theory that states this has already happened."
    -pvh
  • Prediction (Score:3, Interesting)

    by localman ( 111171 ) on Saturday June 19, 2004 @01:43AM (#9470880) Homepage
    The complexity of all these different particles will collapse into something much simpler when we look at it all from a different angle. Since I can't think of any other way to discover this "different angle", I am in favor of the physicists continuing with the current research methods -- finding more and more new and bizarre particles until it becomes obvious what we're actually looking at.

    String theory, where all particles are just different vibration frequencies of otherwise identical loops of "string", is rather appealing. But it seems we can't quite wrap our math around it yet.

    Of course the universe is under no obligation to be simple or elegant, but it just often seems to be the way -- a random complex thing becomes simple and obvious when viewed in the appropriate context.

    Cheers.
  • Re:Rules (Score:3, Interesting)

    by Mycroft_VIII ( 572950 ) on Saturday June 19, 2004 @04:35AM (#9471333) Journal
    LOL, I believe it. Me I don't often get the big funny odd coincidences(sp?). Just a constant stream of wtf was that little non-sensical oddities, but people who are around me long enough start to notice, and somtimes accuse me of doing it.
    Like I can really cause some of these things.
    Like the time I met somone and was talking about an old friend I hadn't seen in years, in response to his mentioning a friend he'd lost contact with a about year ago. Well a few minutes later we discover we're talking about the same guy. Then as we reach the cash-register (book store, how we met, he was looking for a book) and guesse who was in line ahead of us.I was almost 3,000 miles from home at the time. That's about oddest single incident.
    At the other end is things like doors opening for no reason, all the filliments of a 3-way bulb going out at the same time, and the one that helps my rep around tech: things somtimes just spontaneously start working right again if I do anything not actually harmfull to them, or somtimes just watch a friend try and show me what is wrong before I even touch it.
    It's not like it's every day, just somthing like the last paragraph once or twice a week. And somthing about 2/3 as wierd as the mutal friend thing every year to 18 months. Though come to think of it the rate has almost halved from that since about '95.

    Mycroft

"I've seen it. It's rubbish." -- Marvin the Paranoid Android

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