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SELEX at Fermilab Discovers New Particle

Posted by michael on from the ad-infinitum dept.

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."

7 of 259 comments (clear)

  1. Re:False Alarm by Anonymous Coward · · Score: 5, Interesting

    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...

  2. A good quote by heyitsme · · Score: 5, Interesting
    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:

    • "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."
  3. String theory implications? by jwkane · · Score: 4, Interesting

    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.

  4. Re:Not a stupid question! by Noren · · Score: 4, Interesting
    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 (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(subscription required) entering the atmosphere with energies over 10^20 eV have been detected by Japanese, Russian, and American observers.

  5. Re:Stupid question! by Bingo+Foo · · Score: 4, Interesting
    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.

    --
    taken! (by Davidleeroth) Thanks Bingo Foo!
  6. New discoveries in old data by lildogie · · Score: 3, Interesting

    > 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.

  7. Re:Not a stupid question! by barawn · · Score: 3, Interesting

    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.