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Physicists Discover "Doubly Strange" Particle 260

Tsalg writes "Physicists have discovered a new particle made of three quarks, the Omega-sub-b. The particle contains two strange quarks and a bottom quark (s-s-b). It is an exotic relative of the much more common proton and weighs about six times the proton mass. This is probably one of the last noticeable sub-atomic discoveries made somewhere else than at CERN since LHC is about to start the hunt for the Higgs particle that remains elusive even for the experiment that just discovered the Omega-sub-b."
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Physicists Discover "Doubly Strange" Particle

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  • by Pat Attack ( 1353585 ) on Thursday September 04, 2008 @08:32AM (#24872641)
    Sometimes I think physicists are just making things up. This is one of those times.
  • Excuse Me? (Score:2, Insightful)

    by Anonymous Coward

    This is probably one of the last noticeable sub-atomic discoveries made somewhere else than at CERN since LHC is about to start the hunt for the Higgs particle that remains elusive even for the experiment that just discovered the Omega-sub-b.

    How can you be so sure? It's not like CERN lays claim to all the greatest physicists in the world. Am I the only one that is a bit wary of all the eggs in one basket?

    • by jeremyp ( 130771 ) on Thursday September 04, 2008 @08:46AM (#24872805) Homepage Journal

      That was my immediate thought too. Perhaps LHC emits some sort field that causes all other particle accelerators to mysteriously stop working. Yes, that must be it. European particle physics experiments are heavily influenced by fundamental particles called eurons and LHC has been sucking them up at a vast rate to the detriment of other experiments.

      • Re:Excuse Me? (Score:5, Interesting)

        by oldspewey ( 1303305 ) on Thursday September 04, 2008 @08:54AM (#24872895)

        Perhaps LHC emits some sort field

        In Richard Florida's book Who's your city? he actually gets into various theories about how centers of excellence (whether fashion, IT, finance, science, etc.) tend to create a self-reinforcing "buzz" that draws in more and more talented people, and the intellectual atmosphere and other elements of creative infrastructure then allow those people to achieve at a higher level than they otherwise could.

        So according to that theory, yes, the LHC does emit some sort of field ...

        • Re: (Score:3, Interesting)

          by moosesocks ( 264553 )

          There's also the funding issue. Largely due to being (mostly) redundant to the LHC, Fermilab's big accelerator, the Tevatron is shutting down next year.

    • by eln ( 21727 )

      If history has taught us anything, it's that when someone predicts the end of scientific discoveries, they are invariably 100% correct.

    • It would be amusing if the Higgs particle was discovered before CERN really had a go at it. It may be far from the only experiment the LHC is designed for, but it is also the most publicised.

      • Re:Excuse Me? (Score:5, Informative)

        by The_Wilschon ( 782534 ) on Thursday September 04, 2008 @09:36AM (#24873439) Homepage
        Won't happen. We're hard at work on it right now (except when we're reading slashdot...), and we're making some amazing leaps forward in analysis techniques, but we simply won't have enough data to be sufficiently sensitive to the Higgs by the time the accelerator shuts down. We might find evidence or even strong evidence, but not strong enough to call it discovery. We do have enough data to exclude certain mass ranges, however. When you combine our data with D0's (the experiment that did the analysis in TFA), we have enough sensitivity to say that the Higgs, if it is the standard model Higgs (and the lightest SUSY Higgs is sufficiently similar that this holds for it, too), does not have a mass quite close to 170 GeV (which is pretty close to the mass of the top quark, incidentally). http://www-d0.fnal.gov/Run2Physics/WWW/results/prelim/HIGGS/H64/ [fnal.gov]
    • Re: (Score:3, Informative)

      He's talking about the energy levels produced at CERN. While scientists anywhere will be making discoveries, it will likely be with data produced from experiments at CERN.
  • by Instine ( 963303 ) on Thursday September 04, 2008 @08:33AM (#24872649)
    Can someone translate that last sentence for me?
    • by morgan_greywolf ( 835522 ) on Thursday September 04, 2008 @08:52AM (#24872879) Homepage Journal

      Sure. Quarks are one of the two basic building blocks of matter, the other being the lepton. This particular particle -- a baryon, since it is comprised of three quarks -- consists of two strange quarks and one bottom quark. Strange quarks and bottom quarks are both very unstable. Another example of a baryon is the proton, which contains two up quarks and and a down quark. Up and down quarks are generally, by comparison, very stable. The instability of the quarks make this particular baryon difficult to detect.

      • Re: (Score:2, Funny)

        by Anonymous Coward

        Good explanation. GP: It is worth noting that the guy who came up with the names for quarks was obviously on acid while doing so (a requirement for understanding this stuff), so don't worry if the names don't make sense to you. A 'strange' quark is not really any stranger than, say, a bottom quark.

      • by Anonymous Coward on Thursday September 04, 2008 @11:42AM (#24875607)

        Call me when they put together the particle consisting of 2 up quarks, 2 down quarks, a left quark, a right quark, a left quark, a right quark, a 'b' quark, an 'a' quark, a 'select' quark, and a 'start' quark. ;)

    • by eln ( 21727 ) on Thursday September 04, 2008 @09:00AM (#24872969)

      For reference, the last sentence is:

      This is probably one of the last noticeable sub-atomic discoveries made somewhere else than at CERN since LHC is about to start the hunt for the Higgs particle that remains elusive even for the experiment that just discovered the Omega-sub-b.."

      It's really quite simple to translate. It means that this will be the last noticeable sub-atomic discovery made anywhere other than CERN, because other sub-atomic discoveries are going to be way, way too small to be noticeable. However, CERN is in Switzerland, where people are used to working with very, very tiny things like watch mechanisms, and so are more likely to notice these very tiny particles.

      The Higgs particle is simply another name for the "Higgs boson", which is a mythical creature said to roam the forests around CERN, although it may have just been a side effect of the earlier LSD experiments at that location. The Higgs boson is said to be 7 feet tall with bright red hair, red nose, and giant shoes (hence the name "boson", after Bozo the Clown).

      The Omega-sub-b, of course, is supposed to mean the "Omega-sub-basement", which is a room deep under the FBI building where J. Edgar Hoover used to keep his "alternative" wardrobe, but the submitter appears to have died while in the middle of composing the sentence.

      I hope this clears things up for you.

      • This is probably one of the last noticeable sub-atomic discoveries made somewhere else than at CERN since LHC is about to start the hunt for the Higgs particle..."

        Oh see I read that as, "Since the universe, or at least our corner of it, will end as soon as they fire up the LHC"

        I'm actually attending a "Party at the End of the Universe" to celebrate our last days as a species. A terrestrial version of Pan Galactic Gargle Blasters will be served.

    • by florescent_beige ( 608235 ) on Thursday September 04, 2008 @09:01AM (#24872993) Journal

      Can someone translate that last sentence for me?

      Done:

      Dit staat waarschijnlijk een op het punt van de laatste merkbare sub-atomic ontdekkingen ergens gemaakt dan bij CERN anders aangezien LHC is de jacht voor het deeltje te beginnen Higgs dat zelfs voor het experiment ontwijkend blijft dat enkel omega-sub-B. ontdekte.

      • Re: (Score:2, Informative)

        by hkz ( 1266066 )

        Oh man, you get my Dutch Grammar Nazi going on ;-)

        I assume you meant something like:

        "Dit is waarschijnlijk een van de laatste opvallende subatomische ontdekkingen die ergens anders gemaakt worden dan CERN, aangezien de LHC op het punt staat de jacht op het Higgs-deeltje te beginnen, dat ongrijpbaar blijft zelfs voor het experiment dat zojuist het Omega-sub-b deeltje heeft ontdekt..."

        Yeah, that sentence is a b*tch in Dutch too...

    • by perspectival ( 906492 ) <zabinac@@@nc...rr...com> on Thursday September 04, 2008 @09:56AM (#24873823)

      This is probably one of the last noticeable sub-atomic discoveries made somewhere else than at CERN since LHC is about to start the hunt for the Higgs particle that remains elusive even for the experiment that just discovered the Omega-sub-b.."

      In actual English--with tenses--as it used to be used (which is now, as is evident, archaic):

      "This recent discovery [of the Omega-sub-b particle] will probably be the last *notable* subatomic discovery made before the Large Hadron Collider at CERN begins to operate, which is scheduled to happen in October of this year. The LHC will be used to hunt for the Higgs Boson, which has thus far remained undetectable, even by experiments such as this one, which managed to find the Omega-sub-b particle."

      * The author's clever-at-first-glance use of the adjective "noticeable" fails because it applies to "discoveries," and discoveries rarely go unnoticed, unlike grammar.

  • Quark (Score:2, Funny)

    by Anonymous Coward
    Scientists' current model of the structure of a quark here [wikimedia.org] Imagine three of those things!
  • Hmm, ... (Score:5, Funny)

    by Loibisch ( 964797 ) on Thursday September 04, 2008 @08:34AM (#24872671)

    ...that's strange.

  • "This is probably one of the last noticeable sub-atomic discoveries made somewhere else than at CERN since LHC is about to start the hunt for the Higgs particle that remains elusive even for the experiment that just discovered the Omega-sub-b.."

    Easy on the sentence structure, fuller, you're gonna wet the bed.
  • by LotsOfPhil ( 982823 ) on Thursday September 04, 2008 @08:41AM (#24872751)
    Hmm, I think that this is only a relative of the proton in that it too is a baryon (3 quarks). A proton is up-up-down, and this is strange-strange-bottom.
    The charge on the new one is -1, the charge on a proton is +1.
  • Strange + Bottom ? (Score:5, Interesting)

    by florescent_beige ( 608235 ) on Thursday September 04, 2008 @08:43AM (#24872773) Journal

    Ok I thought quarks, leptons, and neutrinos were grouped like this:

    Group 1: quarks; Up & Down, lepton; electron, neutrino; neutrino

    Group 2: quarks; Charm & Strange, lepton; muon; neutrino; muon neutrino

    Group 3: quarks; Top & Bottom, lepton; tau, neutrino; tau neutrino

    So this newly discovered particle is made of quarks from two groups, the strange quark from group 2 and the bottom quark from group 3. Has that been seen before? I never knew it happened.

    • by Anonymous Coward on Thursday September 04, 2008 @08:56AM (#24872935)

      Yes, it's been seen before. There's an ungodly amount of particles (even if you restrict yourself to baryons), in fact, including many weird ones - see http://en.wikipedia.org/wiki/List_of_baryons for instance, or locate a copy of the Physics Letters B/Review of Particle Physics, which dedicates ~150 pages to listing baryons (in my 2004 copy, that is; chances are it's even more today).

    • Re: (Score:2, Interesting)

      The article mentions a periodic table of Baryons. I was just checking that out and there are all kinds of combinations that contain quarks from more than one group, and even one that contains one from each of those groups. That doesn't mean they will all be discovered, but it looks like they're well on their way.

    • by n1ckml007 ( 683046 ) on Thursday September 04, 2008 @09:28AM (#24873311)
      Ok so what about: up up down down left right left right b a start ?
  • In other news, Slashdotters discover Newspeak is creeping in.
  • The last sentence... (Score:2, Interesting)

    by chr1sb ( 642707 )
    ...doesn't make sense, not least because TFA notes that 13 out of 20 predicted baryons have been observed, leaving 7 still to be discovered. Surely these will be just as noteworthy as this discovery. Is the LHC the only accelerator capable of creating and observing these remaining baryons?

    Also, to nit-pick, TFA states that the Omega-sub-b travels 1 mm in a trillionth of a second. This seems a little high to me, given that c is about 3*10^8 m/s = 3^10^11 mm/s. Rounding errors?
    • by meringuoid ( 568297 ) on Thursday September 04, 2008 @09:05AM (#24873019)
      TFA notes that 13 out of 20 predicted baryons have been observed, leaving 7 still to be discovered. Surely these will be just as noteworthy as this discovery. Is the LHC the only accelerator capable of creating and observing these remaining baryons?

      Who knows? Perhaps that's why they're yet to be discovered: that we haven't reached the right energies. Well, the LHC will reach far higher energies than anything else on earth. Every time there's been a substantial step up in collision energies, all manner of new particles fall out. That alone makes the LHC favourite to dominate the field for the foreseeable future. That's before you consider the fact that a project of this scale, with absolutely enormous long-term funding, attracts everyone. The best particle physicists in the world are going to be attracted to working on the LHC, or on analysis of the data it produces.

      There'll still be discoveries made elsewhere, but for the headline stuff, watch CERN.

    • by Detritus ( 11846 ) on Thursday September 04, 2008 @09:17AM (#24873165) Homepage
      Time dilation. Muon decay from cosmic rays is a good example of this.
    • TFA states that the Omega-sub-b travels 1 mm in a trillionth of a second. This seems a little high to me, given that c is about 3*10^8 m/s = 3^10^11 mm/s.

      Following up the second part of your post: It's 3.3x10^-12 [google.co.uk] seconds per millimetre. That puts this particle at about a third of the speed of light.

      • Re: (Score:3, Interesting)

        by meringuoid ( 568297 )
        That puts this particle at about a third of the speed of light.

        No it doesn't, I forgot I'd taken the reciprocal. It puts it at about three times the speed of light. I'd guess the other poster is right, then, and that time dilation prolongs its lifetime.

  • Lamen (Score:4, Interesting)

    by tom17 ( 659054 ) on Thursday September 04, 2008 @08:50AM (#24872861) Homepage

    OK, so I have been reading a lot about particle physics lately and find the whole subject fascinating, but there is one thing (amongst many things) that I am not quite understanding. I have looked it up and my understanding of particle physics is not "there" yet, or at least not enough to grasp this particular concept. Maybe I have just not read the right explanation.

    Can someone in here put it in a simple lamen explanation?

    The question is this:

    This Omega-sub-b particle contains two strange quarks and a bottom quark and weighs about six times the mass of a proton.
    A proton contains 2 up quarks and one down quark.

    Strange quarks have a mass of 95MeV, bottom has 4.2GeV so the total mass of the Omega-sub-b would be 4.39GeV
    Up quarks have a mass of 3MeV, down has 6MeV so the total mass of a Proton would be 0.012GeV

    This would put the Omega-sub-b at 365.8 times the mass of a Proton.

    So I am obviously not understanding how the masses of the quarks correlate to the masses of the fermions. What am I missing here?

    Thanks,

    Tom...

    • Re:Lamen (Score:5, Informative)

      by Ihlosi ( 895663 ) on Thursday September 04, 2008 @09:02AM (#24872997)

      So I am obviously not understanding how the masses of the quarks correlate to the masses of the fermions. What am I missing here?

      IANAPP (particle physicist), but I guess you're missing the equivalent to the "binding energy". Just like the mass of an atomic nucleus isn't equal to the sum of the masses of the protons and neutrons in it.

      • by tom17 ( 659054 )

        Just like the mass of an atomic nucleus isn't equal to the sum of the masses of the protons and neutrons in it.

        it isn't? (approximately).

        I need to go back to basics...

        Tom...

        • I think Spock said it best when he said, "Sometimes the mass of the many does not outweigh the mass of the one"
        • Approximately, it is, if your approximation is vague enough. Since it's that difference that makes nuclear fusion *and* nuclear fission both possible, it has to count as a pretty significant difference, though.

          • by tom17 ( 659054 )

            OK, the binding energy is where it's at then. Just mentioning the concept of that, and the discrepancies between atomic mass and the mass of the fermions, suddenly makes the "magical" bit of fusion/fission much more clear to me.

            I now know where to commence my reading. Thanks!

            Tom...

        • by bucky0 ( 229117 )

          Yeah, binding energy is what we harvest in nuclear fission or fusion.

      • IAAPP, and you got it in one.
    • Re: (Score:3, Informative)

      by MrMr ( 219533 )
      I'm guessing: E=mc^2.
      See for instance here [gsu.edu]
    • Re: (Score:3, Insightful)

      by Keith_Beef ( 166050 )

      Read this: http://en.wikipedia.org/wiki/Hadrons [wikipedia.org]

      Note that the mass of a hadron has very little to do with the mass of its valence quarks; rather, due to mass-energy equivalence, most of the mass comes from the large amount of energy associated with the strong nuclear force.

      To me, this seems to mean that you do not simply sum the masses of the quarks that make up the hadron (a baryon being a kind of hadron).

      The image of a proton given in Wikipedia (http://en.wikipedia.org/wiki/Image:Quark_structure_proton.svg) represents the three quarks in a triangle. OK, so this is simply a convenient representation, but it may help to think of the masses of the quarks as being vector forces. E.g., 10GeV in one direction + 5GeV in the opposit

      • by tom17 ( 659054 )

        Yeah I had read that before, but that aspect must have skipped past my mind last time. I feel I am still held back by the physics I was taught in school in the 80's. Lots of concepts taught in school back then make it harder to visualise the currently accepted concepts. I need to start with a blanker canvas in my mind. I'm still stuck on spherical valence shells and other such simplicities, as it's what I was taught. Trying to get there though.

        What are they teaching in schools now? I should be having a litt

    • One thing you seem to be missing is the letter Y from the word laymen [grin]. But, to answer your question, electron volts are a measure of energy, not mass.
    • Brief explanation (Score:5, Informative)

      by Anonymous Coward on Thursday September 04, 2008 @10:01AM (#24873943)

      The proton weighs a little under a GeV, most of which is binding energy. Since the u and d quarks have so little mass, you can effectively ignore it and look at the dynamical relationship of 3 bound quarks. This is why early models which treated protons and neutrons as different states of the same particle (called isospin symmetry) worked so well. The equation's not all that simple, since binding energy is itself a function of the masses of the quarks involved. The only real theoretical calculations are heavily computational lattice QCD simulations, and experiments like this are a good test of those calculations.

      As a sidenote, the headline makes very little sense. We observed a "triply-strange" particle, the original Omega, ages ago. What makes this special aren't the two s quarks per se, but their appearance alongside a bottom quark.

      IAAPP

    • Re: (Score:3, Interesting)

      by thrich81 ( 1357561 )
      I haven't seen a really suitable answer to your question so I'll give it a try -- I'll use the analogy of protons, neutrons and helium nuclei since they are more familiar. The sum of the masses of two free protons and two free neutrons is larger than the mass of a helium nucleus. The bound combination of the four particles as helium has a lower energy state than the four free particles (due to the attraction they have for each other by the nuclear Strong Force and quantum effects). The difference in the
    • Re: (Score:3, Informative)

      Strange quarks have a mass of 95MeV, bottom has 4.2GeV so the total mass of the Omega-sub-b would be 4.39GeV Up quarks have a mass of 3MeV, down has 6MeV so the total mass of a Proton would be 0.012GeV

      It's not quite so simple. The masses of the baryons are usually dominated by the binding energy (i.e. in the 'gluon' field) and not by the masses of the constituent quarks. The proton/neutron are the extreme case where almost all their mass is from binding energy. Estimating the mass of the quarks themselves is a very tricky business; since you cannot observe free quarks, you have to infer their effective mass in bound systems. An up quark in a baryon (bound system of 3 quarks) has a different effective

  • by Anne_Nonymous ( 313852 ) on Thursday September 04, 2008 @08:51AM (#24872869) Homepage Journal

    ...doubly strange, some quirks, and six times overweight.

    Ed, you're famous!

  • by RTHilton ( 1343643 ) on Thursday September 04, 2008 @09:00AM (#24872973)
    Must be an American particle.
  • static? noise? (Score:3, Interesting)

    by acvh ( 120205 ) <geek@msci[ ]s.com ['gar' in gap]> on Thursday September 04, 2008 @09:04AM (#24873015) Homepage

    They looked at 100 trillion pieces of data, and found 18 that they could call Omega-sub-b. Wouldn't this fall into the realm of randomness?

  • Three Quarks ? Odo will not be happy to hear about this :(

  • Oh no! We're going to destroy the fabric of subspace [memory-alpha.org] before we even develop warp drive! We'll never make it to the stars now!

  • Countdown to the end of the world:
    6 days and counting....

    At this point I would like to say I've enjoyed reading Slashdot for the past few years.

  • I stop thinking about all these particles and fall back to the Stevens (as in George 'Kingfish' Stevens) model of atomic structure: protons, neutrons, fig newtons, and morons.
  • It's "quarky!" It's "quarkalicious!" It's three times the quark of the leading particle!
    Let's face it marketing hype and physics just don't mix!
  • by Taibhsear ( 1286214 ) on Thursday September 04, 2008 @09:55AM (#24873807)

    I was always fascinated by particle physics but it's been a while since I studied it. Can someone explain how a proton-antiproton collision (u,u,d quarks and anti-u,anti-u,anti-d quarks) could produce strange quarks? I thought all that was left after a matter-antimatter collision was x-rays and gamma-rays.

    • Re: (Score:3, Informative)

      by Anonymous Coward
      What you get after anti-matter/matter collide is lots of energy. E=mc^2 so you can also get particles.
    • by jstott ( 212041 ) on Thursday September 04, 2008 @12:01PM (#24875937)

      I was always fascinated by particle physics but it's been a while since I studied it. Can someone explain how a proton-antiproton collision (u,u,d quarks and anti-u,anti-u,anti-d quarks) could produce strange quarks?

      There are three fundamental forces that matter in a particle collider: the strong force, the weak force, and the electro-magnetic force. When the interactions are through the strong force (which is described by the theory of quantum chromodynamics [QCD]), the result is either things start to stick together or you create a pairs of quarks (a quark and its anti-quark, to conserve charge). These quark pairs can, in turn, either produce new pairs of quarks or they can stick and produce new particles. So, strong interactions can produce strange quarks out of nothing if you supply enough energy, but they'll always come in a strange/anti-strange pair. Given that the \omega_b has both a strange and an anti-strange quark in it, I'm guessing that it probably is coming out of a series of strong nuclear interactions.

      At low energies, electro-magnetic forces deal with the interactions of particles and photons, which is important but kinda boring (at high enough energies life is more complicated and EM forces become a kind of weak force, but that's getting off track).

      The final force, the weak force doesn't interact very strongly with particles (hence its name), so weak events are much less common than strong events. On the other hand, because they obey different symmetries, weak events can do some things that strong events can't do. In particular, weak events can change the flavor of quarks, for example, from a down quark to a strange quark. So, the second way you can get a strange quark from a bunch of up and down quarks is through a weak interaction that changes the flavor of one or more quarks.

      -JS

  • by Bemopolis ( 698691 ) on Thursday September 04, 2008 @10:49AM (#24874785)
    Where are all of the scientifically-expert global-warming deniers ready to gainsay this discovery by the obviously-liberal elite particle physics community and their media pawns in the pocket of Big Quantum Chromodynamics?

Every nonzero finite dimensional inner product space has an orthonormal basis. It makes sense, when you don't think about it.

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