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First Observations of Short-lived Pear-shaped Atomic Nuclei

Posted by Soulskill on from the sounds-delicious dept.

An anonymous reader sends this quote from a press release at CERN: "An international team at the ISOLDE radioactive-beam facility at CERN has shown that some atomic nuclei can assume asymmetric, 'pear' shapes (abstract). The observations contradict some existing nuclear theories and will require others to be amended. ... Most nuclei have the shape of a rugby ball. While state-of-the-art theories are able to predict this behaviour, the same theories have predicted that for some particular combinations of protons and neutrons, nuclei can also assume asymmetric shapes, like a pear. In this case there is more mass at one end of the nucleus than the other."

40 of 64 comments (clear)

  1. Followed shortly after by "muffin top" electrons by Picass0 · · Score: 4, Funny

    Not to mention the "poor self esteem" and "great personality" protons

  2. Everything was going great... by Hadlock · · Score: 1

    Everything was going great for the Atomic Nuclei, until it all went pear shaped.

    --
    moox. for a new generation.
  3. Abercrombie & Fitch don't want to know about i by Anonymous Coward · · Score: 1

    If it's pear-shaped, Abercrombie & Fitch don't want to have anything to do with it.

  4. Pear shaped? by DougOtto · · Score: 3, Funny

    It must have gotten married.

    --
    Solving Unix problems since 1989...
    1. Re:Pear shaped? by snadrus · · Score: 3, Funny

      ... the entanglement theory.

      --
      Science & open-source build trust from peer review. Learn systems you can trust.
    2. Re:Pear shaped? by iggymanz · · Score: 1

      silly prude, a nucleus doesn't have get married to get pregnant.

    3. Re:Pear shaped? by Coren22 · · Score: 1

      Um, my perspective on what he said was he was referring to how men (and often women) gain weight when they get married, not just to getting pregnant. Pear shape would imply expanding out in all directions, not just the front.

      --
      APK likes to ask for responses to the same things over and over. Maybe he just likes the responses?
  5. Re:Followed shortly after by "muffin top" electron by Nyder · · Score: 4, Funny

    Not to mention the "poor self esteem" and "great personality" protons

    --
    I'd rather not discuss my atomic weight.

    Talk about a sig that sort of fits in with the convo...

    --
    Be seeing you...
  6. Pear-shaped huh? by Trogre · · Score: 2

    Reminds me of the Gary Larson cartoon set in a haywire factory.

    "Professor, the beam has gone out of alignment, the atom chamber is leaking and the datalogger has crashed again. I'm afraid the whole experiment has gone you-know-what."

    --
    "Nine times out of ten, starting a fire is not the best way to solve the problem." - my wife
  7. Reference to Island of Stablility by Anonymous Coward · · Score: 4, Informative

    For those interested: Nuclei with shapes like this or barbells are significant in solving the problem of filling that range of elements on the Periodic table that were skipped. Ideas were proposed that nuclei would need to have these shapes in order to be stable if the nucleus followed a shell model similar to electron shells. You can read more by researching "Island of Stability"

    http://en.wikipedia.org/wiki/Island_of_stability

    1. Re:Reference to Island of Stablility by DontLickJesus · · Score: 3, Informative

      For those interested: Nuclei with shapes like this or barbells are significant in solving the problem of filling that range of elements on the Periodic table that were skipped. Ideas were proposed that nuclei would need to have these shapes in order to be stable if the nucleus followed a shell model similar to electron shells. You can read more by researching "Island of Stability"

      http://en.wikipedia.org/wiki/Island_of_stability

      Eh, fark. This is mine. Stupid login.

      --
      Where genius and insanity become confused true wisdom is found
    2. Re:Reference to Island of Stablility by VortexCortex · · Score: 3, Funny

      "Island of Stability" -- Well, it's no Fortress of Solitude, but I guess for a used up pear-shaped Atomic Avenger, it'll do.

    3. Re:Reference to Island of Stablility by StripedCow · · Score: 1

      What I find interesting is that apparently we are still not able to simulate a simple system with a few (subatomic) particles. I was under the impression that at least the protons, neutrons and electrons were fully understood, and that simulating a bunch of them would be a breeze.

      --
      If Pandora's box is destined to be opened, *I* want to be the one to open it.
    4. Re:Reference to Island of Stablility by kyrsjo · · Score: 3, Informative

      The problem is that the strong force (QCD) is behaving really weirdly - in effect a proton is composed of an infinite amount of particles: Two up quarks an a down, together carrying most of the momentum (as measured in deep inelastic scattering experiments), a bunch of gluons which, well, glues everything together, and an infinite amount of quark-antiquark pairs.

    5. Re:Reference to Island of Stablility by kyrsjo · · Score: 3, Informative

      This means we can to a certain degree simulate simpler systems, such as pions (composed as an up and an anti-up OR down+anti-down pluss all the gluons and "sea" quarks) using lattice QCD numerical simulations. But for a whole proton, the theory and our computers just aren't up to scratch. For a whole nuclei (which is simplified by "grouping" the quarks into protons and nucleons) it quickly gets VERY hairy as you move up the mass scale. Many-particle quantum dynamics is tough stuff, especially when the interactions get powerfull - and QCD is as powerfull as it gets...

    6. Re:Reference to Island of Stablility by Rob+Riggs · · Score: 1

      Why would an infinite number of quark-antiquark pairs not have infinite mass? Do antiquarks have negative mass?

      --
      the growth in cynicism and rebellion has not been without cause
  8. Radon by justthinkit · · Score: 2

    The image of Ra (Radium) shown is interesting, given that this atom is radioactive...i.e. unstable. With spheres being more stable than wobbly shapes, it seems to make sense that radioactive elements might vary well have asymmetric shapes at the atomic level.

    --
    I come here for the love
    1. Re:Radon by SleazyRidr · · Score: 1

      All I know is that spheres are a lot more stable, but less fun that wibbly-wobbly-timey-wimey stuff. Interestingly though, it looks as though the weird shapes may be more stable than spheres.

      --
      Is 1563649 a prime number?
  9. Make that Radium by justthinkit · · Score: 3, Funny

    Subject line fail.

    --
    I come here for the love
  10. Rugby ball? by Anonymous Coward · · Score: 1

    I'm sure that's immediately obvious to both people who have ever given a shit about rugby and also read slashdot; however "ellipsoid" would be a fuck of a lot more descriptive to most geeks.

    1. Re:Rugby ball? by flayzernax · · Score: 2

      Some of us are Americans you insensitive clod.

    2. Re:Rugby ball? by flayzernax · · Score: 1

      P.S. AMERICA FUCK YEAH!!!...

      all caps count in this case =)

    3. Re:Rugby ball? by MiniMike · · Score: 1

      He should have avoided all controversy and just said that most nuclei have a shape like a football.

  11. That's not pear shaped.... by mortonda · · Score: 1

    it's just big-boned.... :D

  12. Re:Followed shortly after by "muffin top" electron by EdZ · · Score: 1

    Then there's the infamous 'fat electron', which becomes stuck in kinked wiring.

  13. Re:I HAVE RISEN !! by jmrives · · Score: 1

    Co-ed..., now there is an archaic sexist term.

  14. Re:have you considered by c0lo · · Score: 2

    that this nuclei is just more excited than the others!

    Which is why I' really like some details about the experimental settings/procedure.
    The paper's title is "Studies of pear-shaped nuclei using accelerated radioactive beams": is it possible the pear-shape is actually caused by the acceleration?

    --
    Questions raise, answers kill. Raise questions to stay alive.
  15. Re:I HAVE RISEN !! by dotar · · Score: 1

    Could you explain that, please? Where I come from it means someone who goes to a mixed-sex school.

  16. Re:have you considered by dotar · · Score: 1

    is it possible the pear-shape is actually caused by the acceleration?

    is it possible the paper's authors haven't already thought of that?

  17. Re:have you considered by c0lo · · Score: 1

    is it possible the pear-shape is actually caused by the acceleration?

    is it possible the paper's authors haven't already thought of that?

    Do you think this is relevant for my curiosity?

    --
    Questions raise, answers kill. Raise questions to stay alive.
  18. Re:Followed shortly after by "muffin top" electron by meglon · · Score: 2

    Heard in the lab: "Dammit, that neutron went straight to my ass!"

    --
    Fascism: An authoritarian and nationalistic right-wing system of government and social organization. See also: NAZI's
  19. Re:have you considered by Anonymous Coward · · Score: 4, Informative

    The acceleration referred to in the title does not have an effect on that, as it refers to the beam being accelerated before measurements are made (a long time before on the nuclear reaction time scales). The method of smacking nuclei together to excite them then measure the gamma rays produced by the relaxation of the excited nuclei is pretty standard. Although typically it used to be beam of accelerated stable isotopes hitting a radioactive target, and now they are instead accelerating the radioactive isotopes and hitting a stable stationary target. This doesn't have an effect on the reaction/excitation, but instead allows them to use less of the radioactive isotopes for the same amount of reactions, compared to having a large radioactive target most of which is not hit by nuclei in the beam. And obviously the collisions have an effect on the nuclei as that excitation is exactly what they are studying, although in ways that will average over nuclei to prevent random single nuclei effects from affecting the result.

  20. Re:have you considered by c0lo · · Score: 1

    Thanks. Appreciated.

    --
    Questions raise, answers kill. Raise questions to stay alive.
  21. Re:have you considered by Sulphur · · Score: 1

    that this nuclei is just more excited than the others!

    Which is why I' really like some details about the experimental settings/procedure.
    The paper's title is "Studies of pear-shaped nuclei using accelerated radioactive beams": is it possible the pear-shape is actually caused by the acceleration?

    The acceleration of gravity causes my pear shape.

  22. Re:I HAVE RISEN !! by Tablizer · · Score: 1

    and TROLLED !!

    --
    Table-ized A.I.
  23. Fruits and science by Pro-feet · · Score: 2, Insightful

    "...and that, my liege, is how we know the Earth to be banana shaped."

  24. Re:I HAVE RISEN !! by davester666 · · Score: 2, Insightful

    The real implication is that it's OK for guys to bang every chick in sight, but that women that do so are sluts sleeping their way to the top.

    --
    Sleep your way to a whiter smile...date a dentist!
  25. Re:Pear-shaped by SleazyRidr · · Score: 1

    So put your hands up if you’re not to drunk to stand up,
    If you bombing up the toilets put your man up,
    And put your can up spray it in the air mate,
    Check out my man, fuck its all going pear shaped

    --
    Is 1563649 a prime number?
  26. Re:I HAVE RISEN !! by neonKow · · Score: 2

    There's an evolutionary reason for racism too, but we've made much better progress on that front.

  27. Dr Stoyan Sarg predicted this in his BSM-SG theory by Zdzicho00 · · Score: 2

    Dr. Stoyan Sarg already predicted such atomic nuclei shape in his "Basic Structures of Matter - Supergravitation Unified Theory":
    http://www.sbwire.com/press-releases/ground-breaking-new-book-offers-scientific-reasoning-for-cold-fusion-energy-248341.htm

    BTW here is a better article from Physics World:
    http://physicsworld.com/cws/article/news/2013/may/08/nuclear-physics-goes-pear-shaped