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Long-lived Super Heavy Element Created

treeves writes "Radioactive nuclei that hang around for a mere half-minute before falling apart hardly seem stable. Yet compared with the fleeting lifetimes of their superheavy atomic neighbors, the roughly 30-second period that transpired from creation to disintegration of four atoms of a newly discovered isotope of element 108 qualifies those atoms as rock solid. Theoretical physicists predicted years ago that some nuclei of elements much more massive than uranium should survive for a relatively long time — possibly long enough to probe their chemical properties — if they could be synthesized. On the chart of nuclides, theoreticians pinpointed a region with coordinates corresponding to 114 protons and 184 neutrons and indicated that nuclei with those "magic" numbers of subatomic particles should lie at the center of an island of stability. The nuclear longevity, according to the models, is due to the closing of proton and neutron shells, which renders the particles stable against spontaneous fission much the same way that a filled outer electron shell endows noble gases with chemical inertness. Experimentalists, though, haven't yet found a route to reach the center of the island."

14 of 110 comments (clear)

  1. Rest of article by richie2000 · · Score: 4, Informative
    Might as well include the rest of the article too:

    Other theoreticians calculated the effects of subshell closings in other superheavy nuclei. They concluded that an isotope of hassium containing 108 protons and 162 neutrons (270Hs) should survive a long time--much longer than the millisecond or shorter lifetimes typical of most of the heaviest nuclides.

    Now, an international team of experimentalists has detected four of those atoms and probed some of their chemical properties during the roughly 30 seconds the nuclei survive (Phys. Rev. Lett. 2006, 97, 242501). The findings confirm the predictions and provide new statistical data with which such theoretical models can be refined. The team includes 24 scientists from 10 research institutions, including the Technical University of Munich (TUM) and the Institute for Heavy-Ion Research (GSI), both in Germany, as well as institutions in Russia, the U.S., Switzerland, Japan, China, and Poland.

    As TUM graduate student Jan Dvorak explains, the hassium nuclei were formed by firing a high-energy beam of 26Mg projectiles into a target enriched in 248Cm. The target was also doped with a small amount of gadolinium to produce isotopes of hassium's lighter homolog, osmium. Upon formation, nuclear products were exposed to a stream of oxygen. From earlier studies of 269Hs, scientists learned that hassium and osmium--but not other heavy elements--form volatile tetroxides, thereby providing a method for filtering unwanted products.

    In the latest experiments, the volatile oxides were swept into a multistage chromatographic detector, which was cooled along its length in a gradient from room temperature at one end to -150 C. On the basis of the two sets of experiments, 269Hs and 270Hs exhibit distinct nuclear properties but similar chemical properties, as expected.

    The study paints a very consistent picture of that region of the chart of the nuclides and makes clever use of chemistry to sort out an assignment of atomic number, says Kenton J. Moody, a heavy-element research group leader at Lawrence Livermore National Laboratory. Moody adds that the observations support theoretical calculations that scientists have been using to predict transactinide properties and plan superheavy element experiments.
    --
    Money for nothing, pix for free
  2. oh man.... by WillDraven · · Score: 4, Funny
    Posted by samzenpus on Thursday December 28, @03:07AM

    It is the entirely wrong time of day to try to comprehend this one.

    --
    This is my sig. There are many like it but this one is mine.
  3. just wait 1000 years. by macadamia_harold · · Score: 4, Funny

    Theoretical physicists predicted years ago that some nuclei of elements much more massive than uranium should survive for a relatively long time -- possibly long enough to probe their chemical properties -- if they could be synthesized

    In the year 3000, all they'd have to do is follow Nibbler around with a pooper scooper.

  4. Commercial uses? by iMySti · · Score: 4, Funny

    Now is your chance to get the super amazing "30 Seconds to Massive Biceps" weight training program, with new enhanced dumbbells! No refunds after product has stabilized.

  5. The short, happy life of Hassium-270... by Anonymous Coward · · Score: 5, Funny

    Hey, I'm alive! Wow! This is fun! I've got 114 protons... ...and 184 neutrons! I'm surrounded by high-energy beams,
    scientists, and a homolog. Uh, oh! Am I a volatile oxide?!
    No, way! I'm being swept in to a multistage chromatographic
    detector, which is cooled along its length in a gradient
    from room temperature at one end to -150 degrees Centigrade
    (at the other end). But I've done nothing wrong!!!
    Sure, I've got similar nuclear properties to Hs-269, but
    you've got the wrong isotope! Whoa, I'm feeling weird...
    Kind of, uh, uhn, un-s-s-stable... I'm definitely --
    KA-BOOOM!!!

    THE END...?

    (Coming up next: The somewhat longer, happier life of Gadolinium,
    or Osmium -- I'm not sure, because I know nothing about this
    part of the periodic table or nuclear physics!!! LOL!!!)

    1. Re:The short, happy life of Hassium-270... by tom17 · · Score: 5, Funny

      Oh no, not again

  6. Re:More then just theory... by calyxa · · Score: 4, Informative

    I was briefly thrilled the other day about the possibility of counting neutron stars as individual atoms of stable super-heavy elements. I asked my brother, a nuclear physicist, if this was reasonable. he said no, because the neutrons in a neutron star are held together by gravity.

    --
    Decay! Decay! Decay! -Helium
  7. Saving some link-hunting by TravisW · · Score: 5, Informative

    Maybe this should have been: "...Island of Stability..." If you're visually inclined, check out the aptly illustrated "chart of nuclides," showing stability as a function of nucleon counts (i.e. proton and neutron counts).

  8. short supply by MaGogue · · Score: 5, Funny

    Now, an international team of experimentalists has detected four of those atoms ... The team includes 24 scientists from 10 research institutions..

    Back when I was in high school, we'd have to share PC computers at 'computer science' classes, but 1 atom per six researchers.. er, couldn't we increase funding, or something?
  9. Re:Heavy by CookieOfFortune · · Score: 4, Informative
    3. The star gets energy out of fusion up to Iron, after that, it loses energy through fusion though it can still occur, creating the heavier elements. I believe they can determine how much longer a star will survive by measuring the iron content, because once it starts producing a lot of iron, it's running out of hydrogen and helium which act as the most efficient fuel. From the article:

    the hassium nuclei were formed by firing a high-energy beam of 26Mg projectiles into a target enriched in 248Cm. I don't think this is considered "fusion" per se because it does not occur spontaneously like in a reactor and probably uses up a lot of energy. I don't think this in itself is a new technique, as that's how they created some of the other heavy elements.
  10. Elerium-115 ! by S3D · · Score: 4, Funny

    So, how soon can we get Elerium-115 and start building UFO Defence ?

  11. Re:Heavy by kfg · · Score: 4, Informative

    So if we can fuse hige Super Heavy atoms together, why can't we fuse lesser atoms together to make, say, gold?

    We can. In fact, it was one of the first things we did with our new toys It's a fun game.

    It's also very, very expensive.

    KFG.

  12. Re:Heavy by UnxMully · · Score: 5, Informative

    IANAP (I am not a physicist) but I have studied some astronomy including reactions in stars.

    Up to the iron group, fusion reactions are exothermic but produce increasingly less energy, so the higher the mass of the resulting element, the more reactions are needed to produce the energy required to sustain a star.

    Reactions beyond the iron group are endothermic so require energy from the star to complete.

    The other way elements are produced in stars is the addition of neutrons to already existing atoms, hence increasing their atomic mass and producing a different element. IIRC, the energy required to do this is high and exists only in stars.

    There are two types of this reacton, slow and fast. Slow happens in the normal course of events of star evolution where fast happens in the seconds of life during and after a supernova. Elements such as uranium are produced during the fast process. From this, I think these guys have replicated one of the slow/fast addition processes rather than what we tend to call fusion.

    As I say, IANAP but that's what I remember.

  13. Re:Heavy by Dragonslicer · · Score: 4, Informative
    The other way elements are produced in stars is the addition of neutrons to already existing atoms, hence increasing their atomic mass and producing a different element.
    Just to clarify that point, adding neutrons to an atom does not directly produce a different element, it produces a different isotope of the same element. Neutrons can, however, be converted into protons, usually by emitting an electron and an antineutrino (I believe neutrons can also be converted to protons by absorbing a positron and a neutrino, but it doesn't happen nearly as frequently).