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LHC Discovers Pentaquark Particles

mrspoonsi sends news that researchers running experiments at the Large Hadron Collider have published findings confirming the existence of pentaquark particles, first predicted in the 1960s by Murray Gell Mann and George Zweig. The particles consist of five quarks bound together. Further research will examine exactly how this binding works. Previous experiments had measured only the so-called mass distribution where a statistical peak may appear against the background "noise" - the possible signature of a novel particle. But the collider enabled researchers to look at the data from additional perspectives, namely the four angles defined by the different directions of travel taken by particles within LHCb. "We are transforming this problem from a one-dimensional to a five dimensional one... we are able to describe everything that happens in the decay," said Dr. Koppenburg, who first saw a signal begin to emerge in 2012. "There is no way that what we see could be due to something else other than the addition of a new particle that was not observed before."

60 of 95 comments (clear)

  1. Gillette by Anonymous Coward · · Score: 5, Funny

    Gillette: Fuck it, we're doing five quarks!!

    1. Re:Gillette by xxxJonBoyxxx · · Score: 1

      You only think you're kidding.
      https://www.google.com/webhp?q...

    2. Re:Gillette by amRadioHed · · Score: 3, Informative

      He's actually referring to this famous Onion article:
      http://www.theonion.com/blogpo...

      --
      We hope your rules and wisdom choke you / Now we are one in everlasting peace
    3. Re:Gillette by xxxJonBoyxxx · · Score: 2

      I know, but then they DID it. Anyway...

    4. Re:Gillette by infolation · · Score: 1

      Need a shave? Toss out your Bics and grab the Gillette Fusion, which single-handedly represents Consumer Product Event Horizon by combining "the comfort of five blades" (on the front) with "the precision of one" (on the back). The main cutting surface is about the size of a sheet of A4; so large you can't get it under your nose without shearing off your top lip, which is why you need the blade on the back - it's the only bit you can enjoy a reasonable shave with.

      There's also a battery-operated "Power Handle" option that makes the whole thing buzz like a wasp in an envelope - not to help you shave, but to offer yet more fleeting distraction from the UNREMITTING MISERY OF LIFE.

      The Fusion Mk2, out next year, features 190 blades, a 30GB hard drive, a pine nut dispenser and a synthesized voice telling you everything's OK, even though the mere existence of such a razor proves otherwise. I've pre-ordered mine already.

    5. Re: Gillette by silentcoder · · Score: 1

      My then fiance used to have a lot of fun using my fusion's buzz function back as a substitute vibrator back in the day. It was the only use it ever had.

      --
      Unicode killed the ASCII-art *
  2. I for one by Anonymous Coward · · Score: 1

    I for one welcome our exotic matter overlords.

    1. Re:I for one by Anonymous Coward · · Score: 1

      With a crowbar in hand.

  3. This is why physics is the king of the sciences by Crashmarik · · Score: 5, Insightful

    When the mathematics is so powerful that it can make accurate predictions far in advance of their ability to be verified, you know you are connecting with the fundamental mechanisms that drive the universe.

    1. Re:This is why physics is the king of the sciences by CrimsonAvenger · · Score: 4, Insightful

      Either that, or you're not the guy who made the incorrect prediction 50 years back....

      --

      "I do not agree with what you say, but I will defend to the death your right to say it"
    2. Re:This is why physics is the king of the sciences by ConceptJunkie · · Score: 4, Informative

      General Relativity is a shining example of this, and the Standard Model is even more so. These theories are among the most accurate predictors of new discoveries, sometimes ridiculously so.

      Meanwhile, String Theory is still kicking around, getting more and more complex, but coming up with very little in the way of prediction. I'm not busting on it... I keep up with the latest work (as much as a non-expert can anyway) and find it fascinating (and/or incomprehensible).

      We are definitely tapping into something real, but whether or not it's fundamental is another question entirely. Newton seemed fundamental, but wasn't. Einstein seems fundamental, but might not be. It seems like there's usually another layer of reality below the one which seems to be fundamental. But everything we uncover is fascinating.

      I guess what I'm trying to say is, "Science is cool".

      --
      You are in a maze of twisty little passages, all alike.
    3. Re:This is why physics is the king of the sciences by known_coward_69 · · Score: 4, Interesting

      to be fair they have the math worked out for dozens of variants of different theories and need the experiments to confirm which one was right. the original estimates for the higgs boson were all over the place and depending on the energy predicted it would have meant a single dimension, multi-dimensions and lots of other possibilities.

    4. Re:This is why physics is the king of the sciences by omnichad · · Score: 1

      We are definitely tapping into something real, but whether or not it's fundamental is another question entirely. Newton seemed fundamental, but wasn't. Einstein seems fundamental, but might not be. It seems like there's usually another layer of reality below the one which seems to be fundamental.

      We haven't even reached turtles yet.

    5. Re:This is why physics is the king of the sciences by Jason+Levine · · Score: 4, Insightful

      Just to tap into another great scientific discovery, the New Horizons mission is a great example of this also. Nine years ago, scientists had to plan a route and engineers had to design systems. All of this had to be extremely precise. New Horizons had a 100 km by 150 km window of space that it had to be in within 100 seconds. If it was out of this area, the photos would return blank space. While we won't know if it hit the target until the photos come back late tonight/early tomorrow, it looks like they hit the mark. That's planning a route 9 years out and 5 billion km away. That took some serious understanding of orbital velocity to accomplish. One tiny mistake and New Horizons would have wound up far away from Pluto.

      --
      My sci-fi novel, Ghost Thief, is now available from Amazon.com.
    6. Re:This is why physics is the king of the sciences by rubycodez · · Score: 1

      some would argue mathematics is king of the sciences

    7. Re:This is why physics is the king of the sciences by SydShamino · · Score: 1

      Mathematics isn't a science any more than fashion is a science. They are just off the scales at different ends.

      --
      It doesn't hurt to be nice.
    8. Re:This is why physics is the king of the sciences by Crashmarik · · Score: 1

      Most mathematicians would dispute the point and consider the title belittling.

    9. Re:This is why physics is the king of the sciences by bsolar · · Score: 1

      It seems like there's usually another layer of reality below the one which seems to be fundamental.

      Nice to know that the fundamental theorem of software engineering applies to the design of the universe too.

    10. Re:This is why physics is the king of the sciences by DerekLyons · · Score: 4, Informative

      New Horizons had a 100 km by 150 km window of space that it had to be in within 100 seconds. If it was out of this area, the photos would return blank space. While we won't know if it hit the target until the photos come back late tonight/early tomorrow, it looks like they hit the mark. That's planning a route 9 years out and 5 billion km away.

      You left out, as Paul Harvey says, the rest of the story.

      While they planned the route fourteen years ago, they've spent the last nine years (since launch) analyzing the spacecraft's current trajectory and making mid course corrections as needed to ensure that New Horizons hit the window. If they hadn't done so, less than forty minutes after launch New Horizons would have been doomed to miss Pluto entirely. (The booster ended up performing a little 'hot' - when the final stage was discarded, it was actually going too fast.)

      Don't get me wrong, it's still a fantastic achievement that all they needed was 20 m/s (give or take a little) of course correction - but the fact remains that New Horizons wasn't passively ballistic, it was actively flown.

    11. Re:This is why physics is the king of the sciences by shoor · · Score: 1

      I don't so much disagree as consider it a narrow viewpoint. Darwin's Theory of the Origin Of Species by Natural Selection was pretty damn regal in my opinion, and, I daresay, has even influenced the thinking of many physicists. Computer Science has had a big influence too. (I think Computers are the 'steam engines' of the 20th Century in the sense that physicists learned about thermodynamics in the 19th Century from studying the steam engine, which led to all kinds of stuff, and studying what computers can do has had a big influence on thinking and paradigms and what not in the 20th and on into the 21st Century. On top of that computers help physicists compute.)

      --
      In theory, theory and practice are the same; in practice they're different. (Yogi Berra & A. Einstein)
    12. Re:This is why physics is the king of the sciences by Crashmarik · · Score: 1

      Continuous vs Discrete motion. The experiment tells you, your description is flawed.

    13. Re:This is why physics is the king of the sciences by klui · · Score: 2

      Agreed. Here's the page where it shows the significant events of the mission.

      http://pluto.jhuapl.edu/Missio...

    14. Re:This is why physics is the king of the sciences by BlackPignouf · · Score: 2

      "Actively flown" with a one-way latency of 4.5 hours.
      Navigating an oil tanker must feel like go-kart in comparison.

    15. Re:This is why physics is the king of the sciences by neurophil12 · · Score: 1

      Great points, and I fully agree, but I want to go a bit further.

      General Relativity is amazing and wonderful, but I think we can safely say it's not complete or fundamental. Aside from dark matter, the insides of black holes, and quantum effects, it doesn't provide any mechanism for curved spacetime. As much praise as I think Einstein and GR deserve, too often I see and hear people treat it as the ultimate truth of the universe, particularly curved spacetime. I'm somewhat skeptical of String Theory, but I expect some of the mathematics will prove useful in whatever theory emerges successful over the next 30 years or so. For instance, something akin to superfluid vacuum theory, with spinning toroidal vortices as fermions, might well have properties similar to strings.

      I am encouraged by the return of aether in several theories, which shows that the community is slowly getting past the misconception that aether was disproven and discredited when it fact it was one very specific aether theory that was shown to be inconsistent with the evidence. It is challenging, especially for a lay person, so stay on top of all of the theories and experiments, what was disproven, and what alternative theories are actually promising versus those that are silly (particularly when discussed on internet forums). However, we must avoid getting too stuck in one particular paradigm, otherwise it will take that much longer to discover the more fundamental layer of reality that underlies the physics of today.

    16. Re:This is why physics is the king of the sciences by Dcnjoe60 · · Score: 1

      some would argue mathematics is king of the sciences

      Mathematics is not a science. It is a language used to describe scientific principles and theories.

    17. Re:This is why physics is the king of the sciences by rubycodez · · Score: 1

      Because you say so? Oxford dictionary disagrees with you.

    18. Re:This is why physics is the king of the sciences by rubycodez · · Score: 1

      Oxford dictionary: Mathematics: 1. The abstract science of.....

      you lose

    19. Re:This is why physics is the king of the sciences by Dcnjoe60 · · Score: 1

      Because you say so? Oxford dictionary disagrees with you.

      The "study" of mathematics is a science in the broad sense, just like the "study" of theology is also a science. But mathematics itself, particularly as used in the context of this article, is a descriptive language.

  4. There was a God Particle... by funwithBSD · · Score: 1

    so this must the be the Satan Particle.

    --
    Never answer an anonymous letter. - Yogi Berra
    1. Re:There was a God Particle... by Coren22 · · Score: 1

      Naa, just Rosey and her five sisters.

      --
      APK likes to ask for responses to the same things over and over. Maybe he just likes the responses?
  5. PenaQuark? by Caitlin2013D · · Score: 2

    http://i.imgur.com/lkgpKG0.png (stealing someone else's joke but still made me laugh....)

  6. +2/3, -1/3 by bugs2squash · · Score: 1

    So what's the net charge on a pentaquark ?

    --
    Nullius in verba
    1. Re:+2/3, -1/3 by canajin56 · · Score: 2

      "More precisely the states must be formed of two up quarks, one down quark, one charm quark and one anti-charm quark.”

      +1.

      --
      ASCII stupid question, get a stupid ANSI
    2. Re:+2/3, -1/3 by omnichad · · Score: 4, Funny

      two up quarks, one down quark

      Still haven't discovered the Konami quark then, yet?

    3. Re:+2/3, -1/3 by PopeRatzo · · Score: 1

      "More precisely the states must be formed of two up quarks, one down quark, one charm quark and one anti-charm quark.”

      The states also require that there be both bofa and updog.

      --
      You are welcome on my lawn.
    4. Re:+2/3, -1/3 by ClickOnThis · · Score: 3, Informative

      "More precisely the states must be formed of two up quarks, one down quark, one charm quark and one anti-charm quark.”

      +1.

      In detail...
      up quark: +2/3
      down quark: -1/3
      charm quark: +2/3
      anti-charm quark: -2/3

      2/3 + 2/3 - 1/3 + 2/3 - 2/3 = +1.

      --
      If it weren't for deadlines, nothing would be late.
    5. Re:+2/3, -1/3 by bugs2squash · · Score: 3, Interesting

      Thanks - so why don't the charm and the anti-charm go "poof" ?

      --
      Nullius in verba
    6. Re:+2/3, -1/3 by ClickOnThis · · Score: 3, Insightful

      Thanks - so why don't the charm and the anti-charm go "poof" ?

      No doubt they do. Many exotic particles don't have long lifetimes. I'm not sure what the pentaquark's lifetime is.

      The J/psi meson, which consists of a charm-anticharm pair, lives for about 7.2 x 10^-21 s.

      --
      If it weren't for deadlines, nothing would be late.
    7. Re:+2/3, -1/3 by habig · · Score: 1

      Thanks - so why don't the charm and the anti-charm go "poof" ?

      They do, sort of: this thing doesn't last long at all.

      Consider a much more common particle, the neutral pi meson: just two quarks: quark/antiquark pairs of several possible flavors. Also doesn't last long (8e-17s), but extremely well studied.,

    8. Re:+2/3, -1/3 by Pfhorrest · · Score: 1

      IANAP but I would guess that the quantum numbers add up such that it does look like the charm and anti-charm quark went "poof" in some respects (like color charge, I imagine, otherwise I don't see how the chromodynamics can work out with a five-particle system; the color of the anti-charm must be opposite that of the charm, whatever it is, and the remaining three red, green, and blue, respectively, to get a white particle as required by QCD), but left over residual features (like spin and electric charge) in the compound particle that indicates that the charm and anticharm are "in there" somewhere. I don't know enough to guess whether the masses of the charm and anticharm would annihilate and be released in the formation of the pentaquark.

      --
      -Forrest Cameranesi, Geek of all Trades
      "I am Sam. Sam I am. I do not like trolls, flames, or spam."
    9. Re:+2/3, -1/3 by Guy+Harris · · Score: 1

      Thanks - so why don't the charm and the anti-charm go "poof" ?

      They might not be antiparticles of each other, as they might differ in color charge.

    10. Re:+2/3, -1/3 by ClickOnThis · · Score: 1

      Thanks - so why don't the charm and the anti-charm go "poof" ?

      They might not be antiparticles of each other, as they might differ in color charge.

      I think that would violate color confinement because the resulting pentaquark would have a net color.

      --
      If it weren't for deadlines, nothing would be late.
    11. Re:+2/3, -1/3 by Guy+Harris · · Score: 4, Informative

      Thanks - so why don't the charm and the anti-charm go "poof" ?

      They might not be antiparticles of each other, as they might differ in color charge.

      I think that would violate color confinement because the resulting pentaquark would have a net color.

      Red up quark, blue down quark, blue charmed quark, green up quark, antiblue anti-charmed quark. Net color = R+B+B+G-B = R+B+G = colorless. (Shamelessly lifted from the "2015 LHCb results" section of the Wikipedia page for the pentaquark.)

    12. Re:+2/3, -1/3 by ClickOnThis · · Score: 1

      Ah! Thanks for that. After I posted, I wondered if that was possible.

      --
      If it weren't for deadlines, nothing would be late.
    13. Re:+2/3, -1/3 by ClickOnThis · · Score: 1

      Thanks - so why don't the charm and the anti-charm go "poof" ?

      They might not be antiparticles of each other, as they might differ in color charge.

      I think that would violate color confinement because the resulting pentaquark would have a net color.

      Red up quark, blue down quark, blue charmed quark, green up quark, antiblue anti-charmed quark. Net color = R+B+B+G-B = R+B+G = colorless. (Shamelessly lifted from the "2015 LHCb results" section of the Wikipedia page for the pentaquark.)

      Wait ... the two charmed quarks you mentioned are in fact anti-particles.

      Did you mean to swap the blue and green on the charmed and up quarks? That would in fact make the charmed quarks not anti-particles to each other. I'm not sure that's even possible (I'm not an expert on the standard model, let alone pentaquarks) but I assume it would at least not violate Pauli exclusion (because the two up-quarks aren't the same color.)

      --
      If it weren't for deadlines, nothing would be late.
  7. SNL: 1975, SNL: 2000 by CrashNBrn · · Score: 2

    Saturday Night Live 1975: Triple Trac Razor Blade
    The Late Show (1990's): Gillette 3000
    Saturday Night Live 2000: Platinum Mach 14
    The Onion: 2004

  8. Bad day for non planetary science news by pauljuno · · Score: 1

    Any other day this would be so cool for science geeks. But today we're all just waiting for the photos of Pluto to come streaming back to us.

  9. Please Speak English by Anonymous Coward · · Score: 1

    Observations of exotic structures in the J/p channel, that we refer to as pentaquark-charmonium states, in 0bJ/Kp decays are presented. The data sample corresponds to an integrated luminosity of 3/fb acquired with the LHCb detector from 7 and 8 TeV pp collisions. An amplitude analysis is performed on the three-body final-state that reproduces the two-body mass and angular distributions. To obtain a satisfactory fit of the structures seen in the J/p mass spectrum, it is necessary to include two Breit-Wigner amplitudes that each describe a resonant state.

    The biggest problem with modern particle physics isn't String Theory, or Dark Matter, or the costs of experiments. The biggest problem is that particle physicts now speak, consciously or not, in what is effectively a cant. I'm reasonably well educated in physics and mathematics, but this is basically gobbydegook.

    A certain amount of technical jargon is nessesary but this is the abstract. It gets worse further into the paper. I'm seeing this more an more in papers and fields across the sciences. Impenetrable cant. It's a very far cry from the readable and engaging papers once seen even in the middle of the last century.

    The author's should have taken the time to employ the english -- or alternatives -- language but instead I think this abstract was drafted by a committee who forgot that they would be talking to people who weren't themselves. This is the first non-Higgs big result out of the LHC. It's an opportunity to catch wider public interest. Dropping the ball like this and, I suspect, falling back on jargon in lieu of well constructed sentences does a minor disservice to the amount of time and effort spent on these experiments.

    1. Re:Please Speak English by rubycodez · · Score: 2

      Not gobblygook at all, it is perfectly understandable with even undergraduate level knowledge of particle physics.

      Layman's articles targeting high school or less education on this abound, you can find them with search engine.

    2. Re:Please Speak English by Anonymous Coward · · Score: 2, Insightful

      You have stumbled onto the true problem with ignorance: The ignorant refuse to believe they're actually ignorant.

      And the educated know enough to understand the limits of their knowledge and acknowledge their own ignorance, perhaps too much.

    3. Re:Please Speak English by rubycodez · · Score: 1

      "channels" are like slots in a coin changer, they are for counting the different types of decay products. J/psion are one such particle (a charm quark and anti-charm quark bound together)

      https://en.wikipedia.org/wiki/...

    4. Re:Please Speak English by Khashishi · · Score: 1

      You aren't the target audience for the scientific article. That's what the press release is for. Abstracts are not the same as introductions. They are necessarily succinct, to the point where use of jargon is required.

    5. Re:Please Speak English by rubycodez · · Score: 1

      From the quote in the post I was replying to

      "Observations of exotic structures in the J/p channel.."

      Back to grammar school for you I guess

  10. Re:How long till it kills us? by rubycodez · · Score: 1

    That "spatting of atoms", if that's what you want to call collisions with protons (positively ionized hydrogen), happens naturally all the time. Space is spatting you right now with them.

  11. Re:How long till it kills us? by Anonymous Coward · · Score: 5, Insightful

    Why do it? To understand the universe. Knowledge is better than ignorance. Where is the payoff? You're soaking in it. By the end of 1998 (my estimate), ONE spinoff technology of high energy physics--the World Wide Web we are using--had paid for the ENTIRE field, from its VERY BEGINNING up to that time, with interest. The rest since is gravy. You're welcome (IAAPP). What are we going to get by continuing? Well, of what use is a new-born baby?

  12. Re: Sure, we believe you, LRC... by Anonymous Coward · · Score: 2, Insightful

    But a jealous ignoramus would certainly accuse his intellectual superiors of bad faith, rather than accept his inferiority.

  13. What's happened to Slashdot? :) by Xtifr · · Score: 4, Funny

    Ok, three links, one to an actual pre-pub paper, one to CERN's official press release, and one to a reputable news source? What's wrong with this submitter? Don't you know that Slashdot links are supposed to go to some random bozo's blog, where he rants about the political repercussions of a discovery like this, and how it will affect free software/NSA spying/Sharia law/the Lizard people, all with no useful links to any hard data anywhere, but hundreds of ads? :)

    Seriously, I've been expecting this since the recent announcement of a possible tetraquark particle, but I certainly didn't expect it this soon. Very cool.

  14. Re:Sure, we believe you, LRC... by Anonymous Coward · · Score: 3, Insightful

    ... and you wouldn't make shit up about stuff that NOBODY ELSE CAN EVER PROVE DOESN'T EXIST, (since they don't have an LRC and never will), in order to get yet more funding for this bullshit, would you...

    There's nothing more adorable than the special brand of naivete that goes around wearing cynicism's clothes. I could just pinch your cheeks right off.

  15. New Law of Physics by PPH · · Score: 1

    The harder you hit things, the more pieces they break into.

    --
    Have gnu, will travel.