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Science

World's Strongest Magnetic Field Is Demonstrated 55

lazarus_ writes "PORTLAND, Ore. -- Researchers at Florida State University's National High Magnetic Field Laboratory in Tallahassee achieved the holy grail of magnetism recently when their high-temperature superconductor attained the coveted 25-Tesla field strength record."
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World's Strongest Magnetic Field Is Demonstrated

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  • by robdeadtech ( 232013 ) * on Sunday September 28, 2003 @09:26PM (#7081602)
    Metalheads from as far south as Miami, as far north as Atlanta, and as far west as Memphis were seen hurtling through the air at breakneck speed headed toward the city of Tallahassee.

    Tampa, known for it's unusually dense Death Metal population, was particularly hard hit.

  • by G4from128k ( 686170 ) on Sunday September 28, 2003 @09:49PM (#7081693)
    I worked at a place about 17 years ago that was using a superconducting magnet (3-5 T) and the "owners manual" expressly forbade attaching an ohmmeter to the magnet coil to see if the coil had become cold enough to superconduct. The problem was that at even low milliampere currents, the coil could store about as much energy as a photographic flash capacitor. Disconnecting the ohmmeter could create a nasty zap and possibly create a damaging arc inside the coil.

    The field was quite fun if you didn't care about your credit cards. You could feel the eddy current drag on a penny if you moved it in the field and copper rings would fall in slow motion.

    Ah! The good old days!
    • Were you ever subjected to fields strong enough that you felt any biological effects?

      Over in another thread I researched [slashdot.org] a little bit on the known bio-effects of static magnetic fields. I'd be curious to hear first-hand from someone who might have experienced them.

      - Peter
      • Sadly, I never noticed any biological effects, but then we did not climb into the center of the solenoid when it was operating.

        What I would like to see is a magnet big enough and strong enough to levitate a person. I'm sure you've seen the levitating frog [hfml.kun.nl] trick. Now if they could only scale that up because it would be a cool tourist attraction.
        • I saw something very close to that, about 2 years ago, in a newsletter from the Iowa State University physics department; they had one of the profs sitting on a disc of superconducting material that was levitating above a superconducting magnet. Imagine a larger version of the first photo [hfml.kun.nl] on the linked page.
          • Entirely different, of course. The prof wasn't experiencing diamagnetic levitation of his own molecules, but rather levitation of something below him that he sat on in the usual way.

            If the professor were in a very large levitation tube, the magnetic force would be acting on every part of his body uniformly. It's a real gravity-magnetism balanced environment, as you can see here, [hfml.kun.nl] where the water forms a spherical bubble from water tension.

        • I'm sure you've seen the levitating frog trick.

          Wouldn't this cause horrible brain damage? I mean, to a mammal, seeing as how we actually use our brains for most stuff. And, you know, the giant, like alien-sized, magnetic field.

          How big a magnet would you need to use as a weapon, anyway?

    • Anybody want to post a couple formulas? How about the ones you'd need to relate 25 tesla's to mass that it could pull or lift. I'd settle for something that translates it to force.
  • Why do I get the feeling that the following scene will be rather common among the professors present at this event:

    Clerk:"Uh, Sir, the American Express card didn't work either. All of your credit cards are totally blank."
    Scientist Guy: "Son of a BITCH!"

    SCIENTIST GUY then proceeds to consciously attract a crowbar from the Crowbar Aisle to his hands via his newfound magnetic powers and beat CLERK senseless.

    ok maybe not that last part though...

  • While I'm proud of my university this is quite old news. The Lab email announcing this is dated August 23rd. And this has been on ./ before in a slightly altered form: FSU Sets 7 World Records In High Magnetics Research [slashdot.org]
    Of course its still a damn neat achievment.
  • Wesley: Careful with that. It'll rip the iron right out of your bloodstream.

    (P.S. I couldn't find the exact quote online. But I did discover that there is no more depressing thing than ST Voyager based fan fiction. Some of them have completely perfected the stilted dialog. Eugh.)
  • by iannn ( 600593 ) on Monday September 29, 2003 @01:01AM (#7082483)
    Creating a 25 tesla magnetic field is not a big deal in itself. People have been using ~ 40 tesla, pulsed magnetic fields to study superconductors for years. There are also techniques to generate 1000 tesla fields (first reference i googled: http://www.intas.be/catalog/94-3569.htm). They last about a millisecond. How? Well basically, by using explosives. While i only skimmed this article, the peice they are probably leaving out is that they are creating 25 tesla magnetic fields over a large area or for a significant amount of time (more than a second or two). This is really useful and takes tons of energy, so it's an achievement worth mentioning. What i don't understand is why the existence of those other magnets is overlooked, especially since the National High Magnetic Field Laboratory collaborates with lots of people who use them.
  • by guybarr ( 447727 ) on Monday September 29, 2003 @03:38AM (#7082967)

    But higher transient fields have been produced for some time:

    Large Z-Pinches routinely reach 100T, and may, at stagnation, quite conceivably reach fields as high as 10^4 T .

    In laser produced plasmas, magnetic fields have actually been measured to rise up to more than 3*10^4 T :
    Tatarakis et. al. Phys. of Plas. 9/5 pp. 2244 (2002)

  • field reporters have found that a large shipment of faulty electronic equipment has also been sent to the area.
  • by krysith ( 648105 ) on Monday September 29, 2003 @08:34AM (#7084034) Journal
    The article, in addition to being a dupe [slashdot.org], also calls the director of the NHMFL "Jeff Crow". Last time I talked to him, his name was Jack.
    • But remember, when the FBI come calling for our details, Taco and Cowboy Neil promise to go down fighting, just like Butch and Sundance. Hmm, which one's the Butch and which one's the Bitch?
  • How the hell could we get 30 comments in without an Eric Lensher joke?
  • by Anonymous Coward
    World's most screwed up monitor in the office next door.

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