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First Creation of Anti-Strange Hypernuclei 179

Posted by kdawson
from the quark-gluon-plasma dept.
runagate writes "Brookhaven National Laboratory has created a heretofore unknown form of matter. The matter we normally encounter, and are composed of, has nuclei of protons and neutrons that contain no strange quarks. It was known that anti-strange matter could exist, and using the Solenoidal Tracker at Brookhaven's RHIC, scientists detected a couple of dozen instances of antihypernuclei. The 'Z' axis of the Periodic Table has already been extended in the positive direction by the discovery of hypernuclei, but this new discovery extends it in the negative direction for this new type of 'strange' antimatter — which may exist in the core of collapsed stars and may provide insight into why our universe appears to be made almost solely of matter and not antimatter." The Register's coverage reproduces a helpful diagram.
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First Creation of Anti-Strange Hypernuclei

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  • Re:so what happens (Score:5, Informative)

    by Entropius (188861) on Friday March 05, 2010 @01:03PM (#31372560)

    No.

    Strange quarks behave just like down quarks (which are one of the two constituents of protons and neutrons). The only difference is that they have a higher mass.

    Y'know how heavy water is just like light water, except one of the hydrogens is replaced with a deuterium atom? This stuff is similar, except one of the down quarks is swapped with a strange.

    Unlike deuterium, though, these lambda baryons are unstable, because the strange quark is unstable. They can decay by the weak interaction (the same thing responsible for beta decay) into an up quark and a couple of leptons (electrons and neutrinos). The amount of time that weak decays take is very long compared to the time-scales involved in quark physics, but it's still very short compared to a second.

  • Re:so what happens (Score:4, Informative)

    by Chris Burke (6130) on Friday March 05, 2010 @01:18PM (#31372726) Homepage

    That's all good, but the major discovery here is actually anti-hypernucleons made with anti-strange quarks. So yeah, they will annihilate on contact with normal matter just like non-strange anti-matter.

  • by wiredog (43288) on Friday March 05, 2010 @01:20PM (#31372754) Journal

    Preferably while tripping.

  • by maxwell demon (590494) on Friday March 05, 2010 @01:22PM (#31372794) Journal

    ...why is it called a "strange" quark anyways?

    This is slightly off-topic, but from all the names they could have given the damn thing, why give it a bizarre name like that? As if particle physics weren't confusing already...

    From Wikipedia:

    The quark flavors were given their names for a number of reasons. The up and down quarks are named after the up and down components of isospin, which they carry.[48] Strange quarks were given their name because they were discovered to be components of the strange particles discovered in cosmic rays years before the quark model was proposed; these particles were deemed "strange" because they had unusually long lifetimes.[49] Glashow, who coproposed charm quark with Bjorken, is quoted as saying, "We called our construct the 'charmed quark', for we were fascinated and pleased by the symmetry it brought to the subnuclear world."[50] The names "top" and "bottom", coined by Harari, were chosen because they are "logical partners for up and down quarks".[36][37][49] In the past, top and bottom quarks were sometimes referred to as "truth" and "beauty" respectively, but these names have mostly fallen out of use.[51]

  • Re:"Anti-strange"? (Score:4, Informative)

    by MikTheUser (761482) on Friday March 05, 2010 @01:33PM (#31372908)

    Wouldn't an Anti-Strange Hypernuclei just be a Normal Hypernuclei?

    No.

    "Strange", in this context, means "having the attribute of positive strangeness", which means that these hypernuclei are composed of at least one nucleon which, in turn, is composed of at least one strange quark (as opoosed to "ordinary" up and down quarks).

    Thus, "anti-strange" means "having the attribute of negative strangeness", which stands for all the ablove blah-blah, but with "strange anti-quark" inserted instead of "strange quark".

  • Re:so what happens (Score:4, Informative)

    by maxwell demon (590494) on Friday March 05, 2010 @01:33PM (#31372918) Journal

    Except for the anti-strange quark. Since regular matter doesn't contain strange quarks, the anti-strange quark will probably not find a partner to annihilate with, therefore it will live on until it decays into an anti-up, which then can annihilate with an up quark from ordinary matter.

  • by Viol8 (599362) on Friday March 05, 2010 @01:49PM (#31373108)

    Never mind its nuclear differences its:

    Heavier
    Different hydrogen bond strength (which causes toxicity in biological systems in large doses)
    Completely transparent to visible light spectrum - light water is slightly blue due to red end absorbtion
    Different melting/freezing points
    Heavy water ice will sink if put in normal water

  • Re:Honest question? (Score:2, Informative)

    by maxwell demon (590494) on Friday March 05, 2010 @01:57PM (#31373224) Journal

    Anti-matter is matter which has exactly the opposite properties from normal matter (e.g. the proton has positive charge, the antiproton has negative charge). In principle you could build stuff out of it; the problem is that in our matter world that stuff would immediately annihilate with all that matter around. Well, and that we just don't have enough antimatter to begin with :-)

  • by Anonymous Coward on Friday March 05, 2010 @02:19PM (#31373520)

    To you, the headlights will behave exactly as they would were your car "stationary" they will emit light photons which separate from your car at the speed of light -- more on that in a second. To the observer watching your car approach at near the speed of light, your headlights will emit light photons which approach the observer at the speed of light in his reference frame, that fact that you are moving doesn't change that; the velocity of your car and the light emitted doesn't add together -- the light he sees from your headlights will, however, be blueshifted by your approach speed. The reason I put "stationary" in parentheses above is because in your reference frame you and your car are stationary and it is the things you are passing which are moving at near the speed of light. Kind of a poor explanation of Special Relativity in what I wrote -- consult a more authoritative description for a better one.

  • by stillnotelf (1476907) on Friday March 05, 2010 @02:51PM (#31373930)
    That's not the only error in the summary - it also says the 'Z' axis is extended, which is wrong. Z is number of protons. They meant the 'S' axis (for strangeness) has now been extended in the negative direction.
  • Re:Honest question? (Score:4, Informative)

    by sdpuppy (898535) on Friday March 05, 2010 @03:01PM (#31374076)

    Is anti-matter matter? Could we build stuff out of it?

    Consider:

    The theoretical macroscopic properties of antimatter are the same as matter. Interaction with light, gravity, the fundamental forces, entropy would be all the same.

    If you had a world made of anti matter, everything should work the same.

    All electrical charges would be reversed - anti electrons (positrons) are positive charge.

    Anti Protons are negative charge.

    From a distance you would not know that world was made of antimatter, since properties would be the same. Electromagnetic wavelengths absorbed / emitted would be the same. Anti-Sodium would have the same yellow emission line as Sodium.

    However we have not observed antimatter besides as particles. Besides anti-hydrogen, no other anti-atoms (let alone anti-molecules) have been produced or discovered.

    Now building something made of antimatter in a matter world would be quite difficult - close proximity of a positron to an electron and you have neither particle, just a very energetic photons flying away. Any particle coming into proximity of its anti-particle results in annihilation (complete conversion of the masses of the particles to energy).

    Now if Fred meets anti-Fred (ignoring air) they explode not because macroscopic Fred sees his anti-self (no matter how many time you watch that Star Trek episode, it's not true) - it is because Fred is made up or protons, neutrons and electrons and anti-Fred is made up of positrons, anti-protons and anti-neutrons and those little guys go boom.

    How to handle such material that you cannot even get near - and "building" something means manipulating atoms, molecules - uncharged?

  • Re:Honest question? (Score:3, Informative)

    by radtea (464814) on Friday March 05, 2010 @03:30PM (#31374472)

    Not from everything, antiiron could only react with iron, for example.

    Nope.

    Anti-iron would contain anti-protons and anti-neutrons made of anti-quarks and its lepton orbitals would be filled with positrons.

    In the presense of any normal matter--an oxygen atom, say--the electrons in the normal matter would be attracted to the positrons in the anti-matter and they would anihilate, emitting gamma ray photons, leaving the nuclei more-or-less bare. The positively changed matter nucleus would attract the negatively charged anti-matter nucleus, and the various quark/anti-quark pairs would likewise annihilate, producing more photons.

    The thing is, a quark has no clue what kind of nucleus it happens to be in, so the quarks in anti-iron would happily get together with their complements in normal oxygen (or whatever). Annihilation takes place at the elementary particle level, not the baryon (proton/neutron) level.

    So while there would be bits of the anti-iron nucleus left over after it encountered an oxygen nucleus, they would be scattered around and running into other stuff...

  • by Mindcontrolled (1388007) on Friday March 05, 2010 @03:50PM (#31374682)
    Actually, D2O is not generally toxic to biological systems. Multicellular organisms don't exactly like it, but it is possible to grow bacteria and yeasts in heavily deuterated media. It is generally used to produce deuterated proteins for various analytical methods. Bacteria do tolerate 12C and 15N diets rather well, too - of course, the isotopic effect is lower there than for hydrogen. I am not exactly sure where the difference between unicellular and multicellular organisms comes from in that regard.
  • by Grishnakh (216268) on Friday March 05, 2010 @03:56PM (#31374800)

    IANAP, but I'm guessing it has something to do with the fact that the temperatures and pressures inside a collapsed star are far beyond the environment in normal nature, so weird things are bound to happen there, just like weird things happen when we accelerate particles to high velocities in particle colliders and smash them into each other. There aren't very many other places in the universe that we know off offhand where such extreme conditions exist, except for black holes.

  • by Viol8 (599362) on Friday March 05, 2010 @04:20PM (#31375062)

    The difference in hydrogen bond strength affects cell division but also messes about with enzyme and protein operation.

  • by Anonymous Coward on Friday March 05, 2010 @05:00PM (#31375508)

    Actually, that would be DHO not D2O, as only one Hydrogen is deuterated.
    Just doing my duty, keeping Slashdot pedanticism alive.

  • no surprise (Score:3, Informative)

    by Khashishi (775369) on Friday March 05, 2010 @05:50PM (#31376044) Journal

    Essentially, after you get by all the silly nomenclature, (negative strangeness hypernuclei? are you serious?), all it is is confirming what we already knew. For any matter particle, there is a corresponding antimatter particle.

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